ML19341A114

Analysis of Hydrogen Control Measures at McGuire Nuclear Station, Vol 3

ML19341A114
Person / Time
Site:	McGuire, Mcguire
Issue date:	01/05/1981
From:	DUKE POWER CO.
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DUKE POWER COMPANY AN ANALYSIS OF HYOR0 GEN CONTROL MEASURES AT MCGUIRE NUCLEAR STATION VOLUME 3 l

l l

JANUARY 5, 1981

5.

AN EVALUATION OF THE HYDROGEN MITIGATION SYSTEM IGNITER TESTING PROGRAM 5.1 Introduction 5.2 The Hydrogen Mitigation System Igniter Testing Program 5.2.1 Description of Test Equipment 5.2.2 Description of Test Procedures 5.2.3 Description of the Individual Tests 5.2.4 Anomalous Data i

5.2.5 Er ironmental Effects on Igniter Effectiveness ar.d Hydrogen Combustion 5.2.6 Comparison of Tests with the Duke and TVA Igniters 5.2.7 Evaluation of Hydrogen Burning on Equipment 5.3 Fenwal Phase 1 Test Report 5.4 Fenwal Phase 2 Test Report I

l 5-1 i

5.1 Introduction Duke Power ' Company, Tennessee Valley Authority (TVA), and American Electric Fower Corporation (AEP) sponsored an experimental program to determine the effectiveness of the hydrogen igniters which have been installed at McGuire Nuclear Station Unit 1 and Sequoyah Nuclear Plant Unit 1.

This experimental program was conducted by Fenwal, Incorporated in conjunction with Westinghouse and Combustion and Explosives Research Company. The test conditions were selected to present significant environmental challenges to the effectiveness of the igniter so that it could be evaluated.

The experimental program was divided into two phases.

Phase 1 testing was conducted to determine if the hydrogen igniter would cause hydrogen to burn at volumetric hydrogen concentrations of 8,10 and 12 percent for various environmental conditions of pressure, temperature, humidity (steam), and air flow across the igniter.

Phase 2 testing was divided into four parts. The Phase 2, Part I tests were conducted to detemine if the igniter would initiate burning at low hydrogen concentrations for various environmental conditions. The Phase 2, Part 2 tests were conducted to determine igniter performance under the conditions of continuous hydrogen injection with the igniter preenergized. The Phase 2, Part 3 tests were conducted to determine the effect of a water spray on igniter performance at volumetric hydrogen concentrations of 6 and 10 percent and during a continuous injection of hydrogen. One of these tests included a direct water spray on the i'jieter. Phase 2, Part 4 tests were conducted to determine the effect of a single hydrogen burn on equipment typical of that located inside containment.

An igniter assembly identical to those installed at Sequoyah Nuclear Plant Unit I was used for the Phase 1 and Phase 2, Parts 1, 2 and 3 testing. An 5-2

)

i igniter assembly identical tc those installcd at McGuire Nuclear Station Unit I was used for the Phase 2, Part 4 testing.

The results of this Phase 1 and Phase 2 testing indicate the following:

1) Initial pressure in the rance of 6-to-12 psig has no effect on the ability of the igniter to initiate burning at volumetric hydrogen concentrations in the range of 8-to-12 percent.

2) High initial temperatures, in the range of 3500F, have a very small effect on the ability of the igniter to initiate burning.

3) Volumetric steam concentrations up to and including 40 percent steam or environmental conditions of 100 percent humidity do not hinder the ability of the igniter to initiate hydrogen burning.

However, volumetric steam concentrations of 40 percent do suppress the peak pressure generated by a hydrogen burn.

4) Air flow across the igniter in the range of 5-to-10 feet per second does not hinder the ability of the igniter to initiate hydrogen burning. In the higher hydrogen concentration ranges (10-to-12 percent hydrogen) air flow across the igniter has little or no effect. However, at low hydrogen concentrations (6-to-8 percent hydrogen) air flow across the igniter increases the ability of the igniter to burn greater percentages of the I

l available hydrogen.

5) Water spray does not hinder the ability of the igniter to ini6iate hydrogen burning. At low hydrogen concentrations (6-to-8 percent hydrogen) water spray promotes more complete hydrogen combustion just as air flow across the igniter does.

5-3 1

6) The igniter can initiate hydrogen burning at low concentrations of hydrogen during a continuous infection of hydrogen. Continuous injection of hydrogen and steam produce multiple burns similar to those calculated by the CLASIX computer code.

7) The environment produced by a hydrogen burr does not severely affect equipment typical of that located inside containernt.

Tha Fenwal reports describing the resus of the Phase 1 and Phase 2 testing are provided in Sections 5.3 and 5.4.

This experimental program demonstrated that the hydrogen igniters which have been installed at McGuire Unit 1 and Sequoyah Unit I can effectively initiate a hydrogen burn at volumetric hydrogen concentrations of 5 percent and higher.

In the event of an accident resulting in the release of hydrogen in excess of the amount specified in 10CFR 550.44 these igniters will burn the released hydrogen at low concentrations, thereby preventing the burning or detonation of a large concentration of hydrogen.

i 5-4

5.2 The Hydrogen Mitigation System Igniter Testing Program 5.2.1 Descripticn of Test Ecuip:nent A detailed description of the test equipment is contained in Sections 5.3 and 5.4.

During the Phase 1 tests the test configuration was altered slightly after the decond test.

In test Nos. I and 2 the temperature recorded at T3 (see Section 5.3) was sensed and recorded from a thermocouple which m.s n!ver soldered to a bracket similar to the igniter transformer bracket, and reanted inside the igniter box. This thermocouple was replaced with another which would sense the temperature of the air inside the igniter box. This replace-ment was completed prior to beginning the third test, and thereafter there were t

no other changes to the test equipment in Phase 1.

Phase 2 testing was divided into four parts. The instrumentation used in Phase 2, Part I was identical to that used in the Phase I tests Nos. 3 tnrough

14. The test configuration for Phase 2, Part 2 was modified to allow determina-tion of igniter performance under a continuous injection of hydrogen with the igniter preenergized. A ball check valve was added to the injection line and the hydrogen supply bottle was regulated by a rotameter. The output of the rotameter was then connected to the check valve and this completed the test setup.

The only difference between Phase 2, Part 2, test No. 3 and Phase 2, Part 2, test No. 2 was that the hydrogen supply bottle and the steam came together in a " tee connection" which was then attached to the check valve.

The P%se 2, Part 3 tests involved determining the ef fect of a water spray on igniter performance. A spray nozzle was installed in the top of the test vessel.

The flow This nozzle was fed through flexible tubing by a snall water pump.

5-5

from the pump to the nozzle was controlled by a needle valve at the discharge of the pump. The nozzle was designed to produce 700 micron droplets over a 450 half angle at the flow rate of 2 gpm when the pressure differential across the nozzle was 9 psi. Apressuregaugewaslocatednearthenozzieintakeand the pressu.e and flow were confirmed by measurement prior to the igniter tests.

The remainder of the test equipment of Phase 2, Part 3 was identical to that used in Phase 2, Part 1.

However, one of the Phase 2, Part 3 tests was performed with a continuous injection of hydrogen using test equipment as modified for Phase 2, Part 2.

Four additional temperatures were measured for the Phase 2, Part 4 tests conducted to determine the effect of a single hydrogen burn on equipment typical of that located inside containment.

In three tests three thermocouples were loca ed inside and one outside of a Barton transmitter casing.

In two other d

tetts one thermocouple each was located inside and outside of both an Namco limit switch and an Asco solenoid valve.

In addition, a Duke igniter was substituted for the TVA igniter. The major difference between the Duke and TVA igniters is that the Duke igniter has voltage taps whic') allow operation at 10v, 12v, 14v, 16v, or 18v if necessary or desired. The remainder of the test configuration was identical to that used in Phase 2, Part 1.

5.2.2 Descriotion of Test Procedures A detailed description of the Phase 1 and Phase 2 test procedure is provided in l

l Sections 5.3 and 5.4.

l 5.2.3 Description of the Individual Tests 5.2.3.1 Phase 1 Tests The Phase 1 testing program consisted of 14 tests. The igniter relfatty initiated burning in all the tests and the results are tabulated in Section 5.3.

5-6

~

i The following is a description of the distinguishing characteristics of each of 1

i the 14 tests.

Test No.1 - This was a 12 v/o hydrogen test conducted at an initial tempera-ture of 180 F.

It was designed to be used as a bench mark against which the 0

other 12 v/o hydrogen tests could be compared. The AP/aP max (calculated) indicated that it was a relatively complete burn.

Test No. 2 - This was an 8 v/o hydrogen test which was als conducted at an initial temperature of 1800F.

It was also designed to be used as a bench mark against which the other 8 v/o tests could be u pared. However, this test produced a differential peak pressure of 33 psi which was not expected l

l prior to the test. In retrospect this was the first confirmation that an l

8 v/o hydrogen mixture is indeed a border concentration where hydrogen can begin to burn much more completely.

Test No. 3 - This test repeated the same conditions used in test No. 2.

The results, however, differed dramatically. The differential peak pressure was i

only 3 psi in this test and the AP/aP max (calculated) indicated that only partial burning occurred. This was the type of test result which was expected prior l

l to test No. 2.

Test No. 4 - This test was a 12 v/o hydrogen test with steam added. The initial pressure of the test was 6 psig.

It produced a relatively complete burn and a peak differential pressura of 66 psi.

l Test No. 5 - This was an 8 percent hydrogen test with steam added. The initial pressure of the test was 6 psig. This test was unusual in that the pressure trace (see Figure 1) clearly indicates two distinct hydrogen burns.

The pressure in the vessel rose approximately 3.5 psi and then began a smooth 5-7 1

i

climb to a differential pressure of 22.6 psi. No external cause was found for the second or continuous rise to the peak differential pressure.

Test No 6 - This 12 v/o hydrogen test was similar to test No. 4 except that it was run at 12 psig rather than 6.

Results from this test were very similar to those recorded for test No. 4.

Test No. 7 - This 8'v/o hydrogen test generated unusual results due to a break-down in the test procedure. Normally after the hydrogen burn reached its peak pressure and began to descend the igniter was deenergized, and after a small

.down time the mixing fan, located in the bottom of the test vessel, was ct started prior to taking the post-burn sample. However, in this test, the mixing fan was started approximately 30 seconds after the glow plug was deenergized and a second burn occurred (see Figure 2). Previous tests at Singleton Laboratories confirmed that the igniter temperature 30 seconds after being deenergized was still above the 12000F temperature range,and there-fore it was concluded that the igniter rather than the fan initiated the second burn. During the Phase 2 tests this conclusion was confirmed when the mixing fan was started repeatedly in a 6 v/o hydrogen mix but failed to initiate a burn. The results of test 7 were the first indication of the possible positive effects of turbulence in low hydrogen concentrations.

Test No. 8 - This test was designed to determine the effects of fan flow across l

the igniter. This test was identical to the test conditions of test No. 4 l

described above except the addition of a small shaded pole motor fan which was adjusted to move the vessel air at 5 fps past the igniter. The test results were almost identical to those seen in test No. 4 and showed no effect other than delaying the ignitica time for approximately 3 seconds.

Test No. 9 - The test conditions for this test were identical to those in test No. 8 except that the air flow across Ine igniter was increased to 10 fps.

5-8

The test results for this test were likewise almost identical to those in test No. 8 except for the time it took to initiate the burn. This was the longest time that any test went without beginning to burn.

Test No. 10 - This test was very similar to test No. 9 except the hydrogen concentration was lowered to 10 v/o. The position of the fan relative to the igniter was not changed from the previous test and was again confirmed to be producing air flow past the igniter at 10 fps. This test did not show any extended ceiay in initiating the hydrogen burn as was experienced in test No. 9.

Test No.11 - This test was identical to test No.10 with the exception of the fan being relocated to reduce the air flow to 5 fps. The test results, however, were almost identical to those recorded in test No.10.

Test No.12 - This was a 12 v/o hydrogen test which was conducted at an elevated temperature of 3500F and an air flow across the igniter of 10 fps. The peak differeatial pressure seen in this test was almost identical to the peak pressure generated in test No. 11. This indicates that the higher temperature did not affect the completeness of the burn. The time to ignition fcr this test and test Nos. 10 and 11 were very close. This is another indication that the elevated temperature had very little effect.

Test No.13 - This test was another 12 v/o, high initial temperature test identical to test No.12, except that there was no air flow across the igniter.

Tt h test produced peak pressures which were less than both test Nos. 4 and 6 which were similar 12 v/o tests but whose initial test temperatures were 2120F and 160 F less, respectively, than this test.

0 Test No.14 - This test was also conducted at a high initial temperature but with an 8 v/o hydrogen concentration. This test produced a fairly complete burn similar in many respects to test No. 2 and much more complete than the other 8 5-9

l v/o tests (test Nos. 3, 5, and 7) conducted in Phase 1.

5.2. 3. 2 Phase 2 Tests 5.2.3.2.1 Phase 2, Part 1 This part of the Phase 2 testing consisted of nine tests. The first five of the nine tests were designed to determine the igniter combustible limits in the lower hydrogen concentration range. Test Nos. 6 and 7 were designed to I'

determine whether a hydrogen burn is enhanced or hindered by mixture ficw past the igniter. Finally, test Nos. 8 and 9 were designed to determine whether high steam concentration (40 percent) affects flamability in a 10 v/o hydrogen atmosphere. The results are tabulated in Section 5.4.

Test Nos. I through 5 - All five of these tests were conducted in an identical fashion except with decreasing hydrogen concentrations beginning at 9 v/o and ending with 5 v/o. The test procedures used in these tests were identical to those used in Phase 1.

The peak differential pressure began to decrease signi-ficantly around S v/o hydrogen down to a low of.25 psi for tne 5 v/o tests.

The results obtained in these tests confirm that the igniter can effectively ignite hydrogen at low concentrations.

l Test Nos. 6 and 7 - These tests were run in a similar fashion to test Nos. I through 5 with the exception that both tests also included fan induced air flow of 5 fps across the igniter.

In the 8 v/o test the maximum differential pressure was approximately 11 times greater than the corresponding test No. 2 conducted without the fan. The effect of the fan was even more significant in the 6 v/o test where the maximum differential pressure generated by the burn was 14 times greater than the similar test No. 4, conducted without the fan.

I Test Nos. 8 and 9 - These tests were run to determine whether high steam con-centrations (40 percent steam) would affect flammability in both a 10 and 6 v/o 5-10

hydrogen mixture.

In both tests the peak differential pressures were less than those measured in test No. 4 and the equivalent static tests performed in Phase 2, Part 4.

This indicates that the higher steam concentrations act as a pressure suppressant. The time to ignition of these tests did not differ by more than one or two seconds from the equivalent static tests with low steam concentrations.

Test No. 10 - In test No. 9, two burns were observed. The first burn occurred shortly after the plug was energized followed by a second burn when the fan was turned on. This result was similar to that of Phase 1, test No. 7.

It was decided to try and repeat the phenomenon which caused the second burn to deter-mine definitely whether a fan spark caused the burn or whether the fan merely brought new fuel in contact with the is. iter allowing a second ignition.

Initially the vessel was loaded as prescribed for test No. 9.

At this point, instead of energizir] the igniter, the fan was switched on and off several I

times. No burn resulted. After the plug was energized, a small burn (AP =

1 0.2 psi) resulted. After a period of time, the fan was turned on and a larger burn (aP = 3.2 psi) occurred.

5.2.3.2.2 Phase 2, Part 2 Experiments were run to determine igniter performance under continuous injec-tion of hydrogen with the igniter preenergized. The results are tabulated in Section 5.4.

Test No. 1 - The first attempt to perform test No. I was not considered valid because after running this test, a leak was discovered in the hydrogen input line near its entrance into the vessel. There was no way to determine how much hydrogen had leaked out and therefore no way to know how much hydrogen was actually fed into the vessel during the test. Thus, there is no way to correlate l

the measured data to the initial conditions. The leak was repaired and the test l

l repeated.

5-11

Test No. 2 - This was a repeat of test No. 1.

It began with the vessel filled with air at 80 F and 14.7 psia. Prior to the test, ti.e glow plug 0

was energized and allowed to reach its steady state temperature. From the j

start of the test, hydrogen was added to the vessel at a rate of 4 scfm for the 15-minute duration of the test. This hydrogen addition rate was selected to approximately scale the rate of addition into the ice condenser containment lower compartment during an S D type transient.

2 Approximately 100 seconds after initiation of hydrogen flow into the vessel, the first of two burns occurred. The first burn was a continuous burn at low hydrogen concentration for about 8.5 minutes. The average concentration in the vessel at the initiation of this burn was about 5 v/o hydrogen based on the time and rate of hydrogen injection. The peak differential pressure of 7.8 psi occurred 11 seconds af ter ignition and was followed by a gradual decrease in the differential pressure to 3.8 psi 8 minates later. The slow pressure decay rate indicates that hydrogen burning was still occurring, though at a decreasing rate.

This pressure behavior indicates a quick burn of about 30 percent of the accumulated hydrogen followed by a continuous burn of a portion of the constant injection flow.

A :ccond burn was indicated at about 11 minutes after ignition by a local differential pressure pwk of 3.6 psi above the preburn pressure. This burn, unlike the first quickly terminated, thus representing only a minor source of heat.

The pressure vs time curve for this test is given in Figure 3.

l 0

The air temperature showed a quick increase from its preignition value of 83 F to its maximum of 3300F approximately 1/2 minute after ignition. After peaking, t

i the temperature showed a slow, nearly linear decrease of 300DF six minutes later.

At this time a slight temperature increase of 200F over the next 1-1/2 minutes occurred. Approximately 8.5 minutes after initiation of the first burn, the 5-12

air temperature showed a rapid decrease, the result of hydrogen burning cessa-tion. Assuming that all injected hydrogen had burned, 80 percent of the oxygen would have been used by 10 minutes. The air temperature vs time plot is illustrated in Figure 4.

The glow plug box interior air temperature showed a continuous increase from 1.030F at the time of ignition to a maximuin of 193 F at the end of the test. At 0

the completion of the test, the temperature had peaked as seen in Figure 5.

0 The glow plug box exterior temperature showed a continuous increase from 83 F at the time of i'nition ;o a maximum of 226 F nine minutes after ignition. After 0

the temperature peak, a rapid cooling of the glow plug box exterior occurred.

This corresponded with the cooling of the air following cessation of hydrogen burning. The glow plug box exterior temperature vs time is illustrated in Figure 4.

Test No. 3 - This test started with the vessel filled with air at 1600F and an initial pressure of 14.7 psia. The test began with the igniter plug pre-energized and the initiation of hydrogen and steam flows of 4 scfm and.3 lbm/ min (2900F), respectively, into the vessel. These flows were maintained for the 15 minute duration of the test. The hydrogen and steam were mixed imediately prior to input.

Nearly 1-1/2 minutes after the initiation of hydrogen and steam mixture flow, the first of a series of eight finite burns occurred. At this time the hydrogen con-centration would have been 4.8 v/o.

In these burns, a maximum differential pressure of 10.15 psi over the preburn pressure resulted. The maximum air temperature was 3670F. These low temperatures and pressures result from the burning of hydrogen at low concentrations and the dissipation of energy to heat sinks between the burns.

l l

5-13

. ~..

As shown on the pressure vs time plot, Figure 6, the pressure peaks had an initial period of 1 minute decreasing to a period of 1/2 minute between the seventh an! eighth burns. The 7.1 psi pressure increase from thefirstburncorrespondstoburningoffabout30percentofthekydrogen present at that time. Assuming this and no additional burn in between would lead to a concentration of 6.3 v/o hydrogen at the time of the second peak.

Alternately, assumirg some continuous burning (about 40 percent of the injec-tion flow) would result in the same concentration being reached at the beginning of the second peak as for the first (4.8 v/o). The general cyclical pattern appears consistent with buildup to a level where a quick partial burn occurs and then burns at an insufficient rate to match the addition between burn peaks. This shortening of time between the peaks could result from either a reduction in burn completeness due to increased steam concentration or possibly to a reduction in the hydrogen concentration required for a quick burn due to the system temperature increase. The maximum total differential pressure of 10.15 psi above the preburn pressure occurred at the fifth peak. The highest pressure change for a pressure peak with respect to its preburn pressure also occurred at the fifth peak with a value of 7.35 psi.

' air temperature vs time curve, Figure 7, shows a net increase in air tem,erature throughout the series of burns with a local temperature peak corresponding to each of the burns. The air temperature increased from a pre-burn temperature of 165 F to a maximum of 357oF at the peaks of both the 0

i fifth and eighth burns. Following the eighth (last) burn, the temperature decreased for the remainder of the test.

The glow plug box interior temperature gradually increased from a preburn temperature of 1670F to a maximum value of 2380F at approximately 11 minutes into the experiment. Corresponding to each of the eight burns is a small local perturbation in the curve with a greater slope indicating higher exterior 5-14

The glow plug box interior temperature vs time curve is temperatures.

illustrated in Figure 8.

The glow plug box exterior temperature increased reburn value of 1500F to a maximum salue of 2650F at 11 minutes from the into the test. This curve is illustrated in Figure 7.

The temperature and pressure results of this test are very close to the expected values in comparison with the previous test when the initial tempera-tures are considered.

5.2.3.2.3 Phase 2, Part 3 A series of tests were run ti detennine the effect of spray upon igniter per-formance. The results are tabulated in Section 5.4.

Test No. 1 - The first attempt to perform test No. 1 was not considered valid because upon completion of the test, a leak was discovered in-the vessel drain line, allowing the vessel to continually relieve pressure during the test.

Correlation, between the initial conditions and measured results was there-fore not possible. The leaking line was fixed and tested, and the test was then rerun.

Test No. 2 - This test was a repeat of test No. 1.

It was a static test with a 10 v/o hydrogen concentration.

Initially, the vessel was filled with air at 14.7 psia and 800F. Hydrogen was added to the mixture until the desired con-centration was attained and allowed to reach thermal equilibrium. The preburn temperature was 82 F.

Ignition occurred 11.59 seconds after the igniter was 0

energized. The resulting burn caused a differential pressure peak of 50.0 psi The time from ignition to peak differential above the preburn pressure.

pressure was.56 seconds. The pressure curve was similar to other static tests.

Test No. 3 - This test was identical to test No.1 except that the hydrogen concentration was reduced from 10 v/o to 6 v/o. A single burn occurred 22 5-15

seconds after the igniter was energized resulting in a peak differential pressure of 31.2 psi above the preburn value. The time from ignition to peak differential pressure was 1.5 seconds. The pressure curve was similar to those in other static tests.

Test No. 4 - This test was the transient hydrogen burn in this series.

It began with an air filled vessel at 14.7 psia and 80 F.

At 1 minute before the D

test began, spray water flow was initiated with a measured average flow rate of 1.9 gpm. Hydrogen flow into the vessel coincided with the beginning of the test and was input at the rate of 4 scfm. Both flows were maintained for the duration of the test. The glow plug was energized at the beginning of trie test.

Approximately 89.5 seconds after initiation of hydrogen flow, the first of two burns occurred. At this time the average hydrogen concentration would be 4.8 percent. The ff'st was a continuous burn at a low hydrogen concentration which resulted in a 3.12 psi difference between the peak and preburn pressures.

The peak differential pressure occurred 6 seconds after ignition and was followed by a gradual decrease in differential pressure to 0.9 psi after 9 minutes.

A second burn is indicated 10.5 minutes after ignition by a local differential pressure peak of 4 psi over the preburn pressure. This burn was not a con-tinuous burn and quickly terminated. The pressure vs time curve for this test is shown in Figure 9.

Test No. 5 - This test was identical to test No. 1 except that the igniter box was inverted to allow spray water to fall directly on the glow plug.

It should be noted that this arrangement is much more severe than would be expected in containment with the rain shield present. This test was included to 5-16

conservatively bound the possibility of spray drops impinging on the igniter heating element due to turbulence.

Approximately 15 seconds after the glow plug was ene gized the only burn occurred. A peak differential pressure of 42.2 psi above the preburn pressure resulted 1.1 seconds after ignition. The pressure curve was similar to those of other static tests.

5.2.3.2.4 Phase 2, Part 4 This series of static tests was performed for the following purposes:

1.

Determine the effect of a hydrogen burn on certain equipment and typical materials inside the containment vessel.

2.

Detennine the temperature response of a Barton transmitter casing and a solenoid valve / limit switch to a hydrogen burn.

3.

Determine the effect of reduced igniter voltage upon the glow plug's ability to ignite hydrogen.

The results are tabulated in Section 5.4.

Test No.1 - This test involved the burning of an air-steam hydrogen mixture at 5.9 psig and 1290F with a hydrogen concentration of 12 v/o. The igniter voltage was reduced from 14.6 to 12 volts. A Barton transmitter casing was placed inside the test vessel for this experiment with three thermo-couples attached to different positions within the casing and one to the outside.

The locations of the internal thermocouples were: Strain Guage (TC No. 2);

Inside Wall (TC No. 4), and Circuit Board (TC No. 5).

5-17

The result of this burn was a differential pressure increase of 60 psi over the preburn pressure and a maximum air temperature of 7100F. The Barton trans-mitter casing reached maximum internal and external temperatures of 1500F and 2300F respectively. The temperature and pressure curves are similar to those of other static tests.

Test No. 2 - This test was identical to test No.1 except that the Barton transmitter casing was enclosed in a space blanket. This space blanket failed during this test and therefore the test results were very similar to those of test No. 1.

Test No. 3 - This test was identical to test No.1 except that an unshielded solenoid valve / limit switch combination was placed inside the test vessel in addition to the Barton transmitter casing. The four additional thermocouples were relocated from the transmitter casing to this new equipment. One thermo-couple was attached on the inside and one on the outside of both the solenoid valve and the limit switch.

The result of this burn was a differential pressure increase of 63 psi over the 0

The solenoid valve preburn pressure and a maximum air temperature of 760 F.

reached maximum interior and exterior temperatures of 2280F and 2400F.

The 1miit switch reached maximum interior and exterior temperatures of 1700F and 235 F, respectively. The temperature and pressure curves are similar to those 0

of other static tests.

Test No. 4 - This test was identical to test No. 3 except that the solenoid 1

valve / limit switch combination was loosely wrapped in a single layer of aluminum foil.

5-18

The result of this burn was a differential pressure increase of 58 psi over the With the aluminum preburn pressure and a maximum air temperature of 7550F.

foil enclosure, the limit switch reached maximum internal and external temperatures of 1380F and 1850F, respectively. The solenoid valve, also enclosed in the aluminum foil, reached maximum internal and external tempera-tures of 1830F and 2500F, respectively. The pressure and temperature curves are similar to those of other static tests.

Test Nos. 5 and 6 - These tests involved the burning of an air-steam-hydrogen' The mixture at 6.4 psig and 1460F with a hydrogen concentration of 10 v/o.

igniter voltage was reduced from 12 volts in test No. 5 to 10 volts in test No. 6 to demonstrate the ability of the glow plug to ignite hydrogen at reduced voltages.

The result of the burn in test 5 was a differential pressure incraase of For 49 psi over the preburn pressure and a maximum air temperature of 790 F.

test No. 6 the corresponding values were 50 psi and 760 F.

In both cases, the 0

pressure and temperature curves are similar to those of other static tests.

Test No. 7 - This test was identical to test No. 3 except that the Barton transmitter casing was enclosed in a single layer of loosely wrapped aluminum foil and the thermocouples were relocated back to the transmitter cusing as in test No. 1.

The result of this burn was a differential pressure increase of 61 psi over 0

With the aluminum the preburn pressure and a maximum air temperature of 135 F.

foil enclosure, the Barton transmitter casing reached maximum internal and external temperatures of 1400F and 1430F, respectively. The temperature and pressure curves are similar to those of other static tests.

5-19

5.2.4 Anomalous Data In the course of performing both the Phase 1 and Phase 2 testing some of the recorded data was a mmalous due to instrument error. The following describes the anomalous data and the reason why that data has not been factored into this evaluation report.

5. 2.4.1 Phase 1 - Inconsistent Data Two of the thermocouple readings recorded in Section 5.3 require some discussion. Test No. 2 seems to have experienced a large temperature rise inside the igniter box. This reading for an 8 v/o test is higher than the previous 12 v/o and is inconsistent with the rest of the recorded data. There-fore Fenwal replaced and recalibrated that particular thermocouple. Also, the thermocouple was silver soldered to a transformer mounting bracket and subsequently was moved to a new location where it was suspended in air inside the igniter box. There are two possible explanations for this abnormally high reading. The first is the possibility of burning hydrogen leaking into the igniter box.

(The box was intentionally not sealed so that this concern could be conservatively bound.) However, the thermocouple measuring the outside of the igniter box measured only 3300F and it was definitely exposed to the hydrogen burn. The second possibility was that the thermocouple was indeed faul ty. Because of this uncertainty this data point was not used.

In test No. 9 the thermocouple reading vessel air temperature recorded an abnonnally low temperature.

It was postulated that water from the condensing steam effectively shorted the thermocouple. Fenwal checked the thermocouple for damage and recalibrated the instrumentation before continuing. The ther-mocouple operated properly theraf ter. Also, in those tests where a substantial and rapid burn occurred (such as all 10 and 12 v/o hydrogen woncentrations) the 5-20

gas temperature increased many hundreds of degrees in a very short time (a fraction of a second in many cases).

In these tests the vessel air ther-mocouple does not have sufficient response time to measure the true gas temperature and should be disregarded as an indicator of maximum gas tempera-In such cases the pressure measurement in conjunction with the ideal ture.

gas law provides an accurate indication of the actual temperature of the vessel gas.

The pressure traces for tests with a fast pressure rise, less than one second, exhibit a sharp narrow spike near the pressure peak. This is due to the pressure transducer being located offset from the vessel in a short pipe. The gas within the pipe is pressurized to near the peak vessel pressure by the time the flame front reaches the pipe inlet. Hence an overpressure results within the pipe as its contents burn and exhaust into the test vessel.

5.2.4.2 Phase 2 Testing During the course of the Part 3 tests, it was noted that many of the temperature vs time plots were of a jagged and highly erratic nature as opposed to the After this generally smooth and rounded plots obtained in previous experiments.

series of experiments was completed, it was noticed that much of the teflon insulation had been burned off the lead wires to the thermocouples, allowing them to short out in the spray. The themocouple wires were replaced and wrapped in aluminum foil before any subsequent tests were performed. No erratic temperature plots were found in the test data for subsequent tests.

For this reason, the temperature data for this series of tests cannot be relied upon as being accurate.

In Part 4, test No. 4 the thermocouple on the outside of the solenoid valve, unlike the other measured equipment temperatures, did not follow the trend of lower temperatures when insulation was used.

Instead, a higher temperature was 5-21

measured for the insulated case than the non-insulated case.

It is suspected that in this instance, the aluminum insulation was in direct contact with the surface thermocouple, thereby allowing a local situation of heat transfer nearly identical to the uninsulated case. This is substantiated by two facts.

0 First, the valve exterior temperature is nearly the same in both cases, 240 F Scrnnd, the valve interior temperature showed a 450F reduction from vs 2500F.

For these 22SOF in the non-insulated case to 1830F for the insulated case.

reasons, the solenoid valfe exterior temperature for the insulated case is considered invalid.

5.2. 4.3 Hydrogen Sampling Throughout the Phase 1 and Phase 2 testing program both pre-burn and post-burn gas samples were taken. The purpose of these samples was to confirm the pre-burn hydrogen concentration inside the test vessel and to confirm the completeness of the burn after the test had been completed. Prior to the start of Phase 1 testing it was decided that the gas samples would be analyzed by an independent laboratory using gis chromatography.

In the majority of the pre-burn sample the gas chromatograph hydrogen analysis did not agree with the hydrcgen concentration believed to be in the test vessel prior to testing.

In an attempt to isolate the problem duplicate samples were Both laboratories agreed that the post-burn samples sent to another laboratory.

contained less than 0.1 percent hydrogen. However, the second laboratory reported hydrogen concentrations in the pre-burn samples which differed from the original laboratory's analysis by more than 1.5 percent and neither laboratory was in agreement with the hydrogen concentration believed obtained by using the partial pressure method of loading the vessel.

Every effort was made to verify that neither the method of taking the samples 5-22

nor the sample bombs themselves was the cause of the discrepancies.

It is not known why the gas chromatograph laboratory reported close agreement (within 0.5 percent) for four of the 14 pre-burn samples in Phase 1 and yet also found one test to be a full 3 percent off the expected hydrogen concentration. Further suspicion of the gas chromatogaaph analysis was created when the TVA test representative brought a pre-burn sample to Singleton Laboratories for analysis using a hydrogen analyzer. This Singleton analysis reported that the sample was within 0.5 percent of the expected concentration.

Due to the uncertainty created by gas chromatograph hydrogen analysis the results obtained from the gas chromatograph laboratory are not being used.

5.2.5 Environmental Effects on Igniter Effectiveness and Hydrogen Combustion The igniter testing program was conducted to determine how effectively the Duke and TVA igniters cculd initiate combustion of hydrogen under the environ-mental conditions expected to exist inside containment aftGr a less-of cooling accident. The program was also designed to determine how these environmental conditions would affect the hydrogen burn once initiated. These environmental conditions include temperature, pressure, humidity (steam), air flow across the igniter (atmospheric turbulence), and presence of water spray droplets in the atmospnere. The parameters of importance in determining the effects of these er.vironmental conditions are burn initiation, burning completeness, peak pressure rise and peak temperature rise.

5.2.5.1 Effects of Temoerature The tests conducted at Fenwal covered a range of initial test temperatures from approximately 130 to 3500F.

In previous tests conducted at Singleton s

Laboratories it was determined that approximately 18 seconds elapsed from the time the TVA igniter was energized to the time it reached approximately 5-23

1200 F.

Figure 10 is a graph of the time to ignite versus initial test 0

temperature for the Phase 1 tests. As the graph indicates there is little or no correlation between initial test temperature and the time required for the igniter to initiate burning.

5.2.5.2 Effects of Pressure The tests conducted at Fenwal ranged in pressure from approximately 17.9 psia to 26.7 psia. Figure 11 is a graph of the time to ignite versus initial test pressure for the Phase 1 tests. The graph indicaces that there is no correlation between the initial test pressure and the time required for the igniter to initiate burning.

5.2.5.3 Effects of Humidity (Steam)

In 21 of the tests conducted at Fenwal steam was injected either prior to or during the test. The quantity of steam and/or saturated conditions inside the vessel was chosen to produce high humidity. The percentage of water inside the, vessel in the form of steam ranged from approximately 6 percent to a high of 40 percent. The results of these tests indicate that high humidity or steam concentrations up to 40 percent have no effect on the ability of the igniter to initiate burning. The primary effect of humidity (up to 40 percent steam) on hydrogen combustion is to slightly increase the lower combustion limit as humidity increases. The primary effect of steam upon hydrogen burning once initiated is to supress the resulting pressure and temperature rises. For those tests with similar initial temperatures and hydrogen concentrations, the thermocouple responses indicate a general trend toward lower observed temperatures with increasing water vapor concentration.

5.2.5.4 Air Flow Across the Ioniter_

Five of the 14 tests in Phase I were designed to test the ability of the 5-24

&a4 PW igniter to ignite hydrogen with air flows of 5 and 10 fps.

In all five of those tests the time to ignition increased.

In Phase 1, test No. 8 the air flow across the igniter was set at 5 fps. This marginally increased the time to ignition by 2-to-4 seconds.

In the very next test, however, the air flow across the igniter was set at 10 fps and the time to ignition increased significantly, to approximately 49 seconds, over the average time to ignition of 18 seconds. This result, however, was not reproduced in the two other 10 fps tests where the time to ignition was 29 and 25.9 seconds, respectively.

It appears that air flow across the igniter retards only the rate at which the igniter heats up but does not prevent the igniter from reaching ignition temperatures.

The introduction of fan induced turbuleare in the test medium served to increase the burn completeness for those burns with initial hydrogen concentrations of 8 v/o and below.

In these cases, the hydrogen immediately arc.nd the igniter burned in a brief burst. Then as the fan remixed the atmosphere, a flammable mixture sas again introduced in the vicinity of the igniter and tna mixture f

ignited Hence for relatively low hydrogen concentrations (4-to-8 percent) fans increase the amounts of hydrogen burned.

5.2.5.5 Effects of Water Sprays The Phase 2, Part 3, tests were designed to determine what effect water spray would have on the ability of the igniter to initiate burning. The test results indicate that rather than hinder the igniter's performance water spray actually increases the completeness of the hydrogen burn at low hydrogen concentrations.

In addition, the time to ignition was not increased by the sprays. The last test in Part 3 involved turning the igniter box over and allowing the 5-25

igniter to be sprayed direct' Even in this severe test the igniter initiated a 10 v/o hydrogen burn in IL 3econds. This demonstrates conclusively that water sprays do not hinder the igniters' ability to initiate burning.

l The introduction of water sprays tends to have two effects upon hydrogen burning.

The subcooled water droplets absorb greater amounts of energy as opposed to merely water vapor and therefore reduce the peak pressures and temperatures which result from the hydrogen burn. The introduction of the sprays also tends to create turbulence which, in turn, increases the amount of hydrogen burned.

l 5.2.6 Comparison of Tests with the Duke and TVA laniters The Phase 1 and Phase 2, Parts 1, 2 and 3 tests were conducted using an igniter assembly identical to those installed at the Sequoyah Nuclear Plant. The Phase 2, Part 4 tests were conducted using an igniter assembly identical to those installed at McGuire Nuclear Station. The major difference between the two igniter assemblies is that the Duke igniter features voltage taps which would allow igniter operation at 10v, 12v, 14v, 16v, or 18v if necessary or desired.

The TVA igniter used in these Fenwal tests was operated at 14.6 volts. The Duke igniter was operated at 12 volts except for Phase 2, Part 4, test No. 6 where it was operated at 10 volts.

Most of the static tests were performed with the igniter voltage at 14.6 volts.

In these tests the igniter initiated burning after an average of 15 seconds.

When the igniter voltage was reduced to 12 volts, the average time to ignition increased to about 27 seconds. For the 10 volt case, ignition time increased to 55 seconds. Thus, it is seen that reducing the igniter voltage increases the time to ignition. This is expected as reduced voltages will increase the time needed for the glow plug to reach high enough temperatures to ignite the hydMgen.

It should be noted that in no case was ignition prevented, but was instead n;erely delayed. Both igniters reliably and repeatedly initiated hydrogen I

I

)

burning.

5-26

^

5.2.7 Evaluation of Hydrogen Burning on Equipment 5.2.7.1 Test Results The Phase 2, Part 4 tests were conducted. with equipment typical of _that found inside containment placed inside the te;t vessel.

In addition, the TVA igniter assembly was subjected to over 30 h.,.',nen burns while the Duke igniter assembly wLs subjected to 7 hydrogen burns. Both igniter assemblies survived repeated hydrogen burns and stili functioned properly. Hydrogen ignition was achieved in every test of Phase I and Phase 2.

Section 5.3, page 8, lists the Phase 1 tests and the four temperateres which were recorded for each of the tests. The tests results indicate that the average temperature rise across the igniter box (T3 - Ty) for the tests run at 12, 10 and 8 percent volumetric concentrations af hydrogen was 480F, 380F and 170F respectively.

In several of the Phase 1,12 v/o tests the vessel air temperature was recorded at 10000F or over.

In all cases the vessel air temperature returned to within approximately 50 F of initial temperature in less than 5 0

minutes. The corresponding air temperature inside the igniter box for these same tests, however, never exceeded the initial test temperature of the vessel by more than 650F.

In Phase 2 it is more difficult to draw comparisons as was done for Phase 1 because fewer identical tests were performed and a meaningful average l

could not be calculated. However, in the Phase 2, Part 1 tests the maximum temperature rise across the igniter box for any of the Part 1 tests was 590F which occurred during a fan induced second burn of a 6 v/o hydrogen mixture.

The Phase 2, Part 2 tests provide larger temperature rises across the box, 1180F for the continuous hydrogen injection / burn case and 780F for the eight peak multiple burn which occurred with the continuous injection of hydrogen 5-27

and steam.

It was expected that these numbers would be higher due to the longer burn duration and the quantity of hydrogen burned. Due to the melting of the teflon insulation on the themocouples the temperature data for Phase 2, Part 3 is suspect.

In the Part 4 tests the thermocouple located inside the igniter box was removed and relocated so that the temperatures measured were the inside and outside of the equipment placed in the vessel for equipment survivability testing.

In those tests the maximum temperatures measured across the Barton transmitter 0

casing, the solenoid valve, and the linit switch were 101, 99 and 41 F, respectively, for exposure to a 12 v/o hydrogen burn.

Table 1 is a list of all the equipment exposed to at least 12 v/o hydrogen burns during the Phase 2, Part 4 tests. These cc,mponents are representative of the critical components needed following a TMI-type accident. The majority of the equipment did not experience any visible signs of degradation. The only exceptions were some paint samples on concrete blocks which showed slight discoloration on the corners and one piece of cable which showed a couple of small (1/2 x 2 inch) scorch spots on the black plastic coating. Table 2 is a list of miscellaneous equipment which was also included in the test vessel during the testing.

5.2.7.2 Effects of Insulation Four of the tests performed in Part 4 were included for the purpos2 of determining the effect of insulation on equipment inside containment during a hydrogen burn.

In test No.1, a Barton transmitter casing was usej which had three interior thermocouples to measure interior air temperature and one thermocouple attached to the exterior to measure surface temperature. The casing was exposed uninsu-lated to a 12 v/o hydrogen burn. This resulted in maximum interior air and exterior surface temperatures of 1500F and 2300F, respectively.

5-28

Test No. 7 was identical to test No.1 except that the Barton transmitter casing was loosely wrapped in a single layer of heavy duty aluminum foil

~

(1.0-1.5 mils thick). The foil wrap had the shiny surface facing outward.

This test resulted in maximum interior air and exterior surface temperatures of 1400F and 1430F, respectively.

In test No. 3, a solenoid valve and limit switch combination was used which had for each component one thermocouple to measure interior air temperature and one themocouple attached to the exterior of the structure to measure surface temperature. The switch-valve combination was exposed uninsulated to a 12 v/o hydrogen burn as in test No. 1.

The results of this burn were maximum solenoid valve interior air and exterior surface temperatures 0

of 228 F and 2400F, respectively. For the limit switch, the maximum interior 0

air and exterior surface temperatures were 1700F and 235 F.

Test No. 4 was identical to test No. 3 except that the solenoid valve and limit switch combination was wrapped in aluminum foil in the same manner as described earlier for the Barton transmitter casing. The resulting maximum solenoid valve interior and exterior temperatures were 1830F and 2500F, respectively. For the limit switch, the maximum interior air and exterior surfaca temperatures were 138oF and 1830F. The interior air terrperatures 0

dropped 450F and 32 F for the solenoid valve and limit switch respectively when insulation was used. The Barton transmitter casing maximum interior air temperature dropped ifF when insulation was used. Likewise, the limit switch exterior surface temperature showed a reduction of 520F when insula-tion was used. The Barton transmitter casing exterior surface temperature 0

showed a reduction of 87 F.

5-29

)

l The solenoid valve exterior temperature is an exception to the trend of reduced temperatures when insulation is used showing a higher temperature for the insulated case than the non-insulated case.

It is suspected that in this instance, the aluminum insulation was in direct contact with the surface thermocouple, thereby allowing a local situation of heat transfer nearly identical to the uninsulated case. This is substantiated by two facts. First, the valve exterior temperature is nearly the same in both cases 2400F vs 2500F. Second, the valve interior temperature showed a 450F reduction from 2280F in the non-insulated case to 1830F for the insulated case. The solenoid valve exterior temperature for the insulated case is therefore considered invalid.

A loosely wrapped single sheet of aluminum foil 1.0 to 1.5 mils thick has little insulating ability, except when convective and/or radiative heat transfer predominates.

It is expented, in this burn case, that radiative heat transfer represents a very significant mode of heat transfer due to the high temperatures which result from the burning of 12 v/o hydrogen concentrations.

Radiative heat transfer would be expected to decrease in significance as a primary mode of heat transfer when the concentration at which the hydrogen turned is reduced (and thus the flame temperature reduced).

For burns at lower hydrogen concentrations, a larger part of the overall heat which was transferred to equipment woul1 be through the vehicles of conduction and convection.

These would not be as greatly affected by a single layer of aluminum foil as radiative heat transie..

5-30

TABLE 1 i

COMPCNENTS PLACED IN FENWAL VESSEL e'

FOR THE EQUIPMENT SURVIVABILITY TESTS No. of Test Efrect Equipment Exposures of Tests 1.

Paint samples (on 1

Very light oxidation riim over concrete blocks) paint, deeper discoloration of excess paint on corners of concrete blocks 2.

Paint samples (on 1

Very light oxidation film ever metal slabs paint 3

BX-type metal conduit 1

No obvious degradation 4.

Black plastic coated 1

Two scorch spots (2" by 1/2")

cable 5

Namco limit switch 3

No obvious degradation 6.

Asco solenoid valve 3

tio obvious degradation 7.

Barton transmitter casing 5

No obvious degradation 8.

Miscellaneous wiring 1

No obvious degradation 9.

TVA igniter asse=bly 30 Assembly still functions well.

Transformer coating scorched.

Transformer wires scorched.

Wrap on transformer windings scorched.

Glow plug connector scorched.

Transformer laminations corroded.

Cover gasket scorched and hardened.

Assembly exterior lightly corroded.

10.

Duke igniter assembly 7

Cover seal burned, but no other obvious degradation 11.

Fischer Regulator 1

No obvious degradation I

l lj

TABLE 2 MISSCELLANEOUS EQUIPMENT IN FENWAL

{',

VESSEL DURING TESTING No. of Test Errects Equipment Exposures of Tests 1.

Wood block (4" x 4" 20 Thin browning over much or wood 5-1/2")

surrace 2.

Thermocouples 40 No obvious degradation 3

Thermocouple lead 30 Terlon insulation burned err most wires (first set) of wires 4

Thermocouple lead ' wires 6

No obvious degradation (second set)(wrapped in aluminum foil) 5.

Spray nozzle 5

No obvious degradation 6.

Fan motor (1st)(1/150 hp 20 Light oxidation over surrace; shaded pole motor) soldered connections railed on last test 7.

Fan motor (3rd)(1/150 hp 1

Failed af ter high temperature shaded pole motor) transient burn test; soldered connections detached i'

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5.3 Fenwal Phase 1 Test Report DETERMINATION OF IGNITION PERFORMANCE CHARACTERISTICS OF GLOW PLUG HYDROGEN IGNITOR FOR WESTINGHOUSE ELECTRIC CORPORATION PITTSBURGH, PENNSYLVANIA REPORT NO. PS R-914 Issued:

November 10, 1980

<t[.//

Prepared by:

/

TA'

^

Warner G. Daldell @

~

Test Engineering Supervisor Protection Systems Division Approved by:

_ /// -

osepff.Gillis

[ManageJion Systems Division Explosion Protection Systems Protect

~-

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS om..

of w.i.., cad. a camp.ny. sac.

5-31

Report No.

PS R-914

SUMMARY

A series of tests have been conducted to ascertain the ignition capablity of a special glow plub ignitor in various mixtures of hydrogen, air and steam.

Comparison of the test results, e.g. pressure and temperature transients due to com-bustion of hydrogen, with previously published information has shown good agreement.

The performance of the glow plug ignitor' in igniting hydrogen mixtures has been consistent with the lit-erature and satisfactory in all respects.

a l

l ar m,2 l} l'N '$?

l

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FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS 0.w.s on of Waher Kidde & Company, Inc.

5-32

Report No.

PS R-914 RES ULTS Test

'H Steam V

6 P, 2

No.

(%)

Added (Ft/S ec)

(PSI) 1 12 No 0

53.00 2

8 No 0

33.00 3

8 No 0

3.00 4

12 Yes 0

66.00 5

8 Yes 0

22.60 6

12 Yes 0

72.00 7

8 Yes 0

16.25 8

12 Yes 5

67.50 9

12 Yes 10 65.00 10 10 Yes 10 53.70 11 10 Yes 5

52.70 12 12 Yes 10 58.75 13 12 Yes 0

60.00 14 8

Yes 0

30.00 Hydrogen Test Concentration (%)

H 2

Steam Added (Yes - No)

HO 2

Air Velocity at Glow Plug (Ft/S ec)

V OP Maximum Pressure Increase (PSI)

Detailed Results are Shown in Table No. 1.

FENWAL INCORPORATED : ASHLAND, NAISACHUSFM Div.s.on of Waiter Kidde & Company, lac.

5-33

s Report No.

PSR-914 l

APPARATUS Tests were conducted in a 1000 gallon spherical test vessel having a pressure rating of 500 psig with the capability o'f being heated to 350 F.

The vessel is constructed of carbon steel with a stainless steel liner.

The outside surface of the vessel was insulated with 3 inch thick fiberglass insulation.

This insulation had an aluminum j

)

foil face which oriented away from vessel.

Mixing of the various gaseous components was accomplished by means of a small shaded pole electric motor fan.

This fan had a 4 inch diameter blade with an air moving capacity of 200 f

CFM.

Steam was supplied to the test vessel from an electrically heated boiler which was self-regulated to maintain a pressure of 40-50 psig.

A manually operated ball valve was positioned between the boiler and the test vessel.

The temperature of the test vessel was controlled by a thermocouple controller which had its sensing element in a well inside the vessel and approximately 18 inches from the vessel wall.

A The temp'erature of the test vessel was sensed and recorded from a thermocouple which was approximately 12 inches below the geometric center of the vessel.

t

~

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS D v.sion of Walter Kidde & Company, Inc.

6 34

Report No.

PS R-914 APPARATUS (Cont'd)

The temperature of the test vessel wall was sensed and re-corded from a thernocouple which was silver soldered to th'e ves-sel inside wall at a point approximately 12 inches below the equator.

Transient pressures were monitored by means of two strain guage-type pressure transducers, the output of which are fed to a Consolidated Electrodynamics Corporation recording oscil-lograph.

Timing markers were electronically superimposed on the oscillograph chart, providing a time base to facilitate the determination of the rate of pressure rise.

One transducer was calibrated to read relatively low pressures resulting from margin-al pressure transients and the other was calibrated to read higher pressures resulting from more complete combustion.

3 mercury manometer was used to measure pressures during the loading of gaseous components by the partial pressure method.

Samples for gas chromatograph analysis were taken from the test vessel, through a cooling / condensing chamber into a 500 ML glass sa:*.ple bulb.

A vacuum pump and various valves were used so as to be able to draw the sample first into the cooling /

l condensing chamber and then into the glass sample bulb.

l

~

Air flow across the glow plug (when specified) was provided l

by a small shaded pole motor electric fan placed on an adjustable l

horizontal mount.

l

/

~

j FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS Dan.an of w her x;dde & Corr 9eay. Inc.

5-35

Rnport No.

PS R-914 APPARATUS (Cont'd)

Precise positioning of the fan was done each time air flow was specified by measuring the air flow at the glow plug wit *,

en Alnor Series 6000-P Velomete" and moving the fan accord'ingly.

This fan had a 4 inch diameter blade with an air moving capacity of 200 CFM.

The temperature of the outside wall of the glow plug box was sensed and recorded from a thermocouple silver soldered centrally on one of the vertical box walls.

The temperature that might be experienced by the glow plug transformer was sensed and recorded from a thermocouple which was silver soldered to a bracket which was similar to the trans-former bracket and mounted inside the glow plug box in a similar location.

(Used in tests No.1 and No. 2).

The gas temperature of the interior of the glow plug box was sensed and recorded from a thermocouple suspended inside the box.

(Used in tests No. 3 through No. 14).

All thermocouples were 24 gauge iron constantan welded junction with teflon insulation.

This apparatus is shown diagramatically in Figure No. 1.

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS D v.s.on of Waleer Kidde & Company, Irw.

5-36

. - ~

Report No.

PS R-914 PROCEDURE Vessel temperature was stabilized at the specified test temperature.

Barometric pressure, relative humidity and ambient temper-ature were read and recorded.

Air, hydrogen and ' steam (when specified) were added accord-ing to the appropriate partial pressure.

The vessel contents were mixed for approximately five min-utes.

The gas sampling apparatus was evacuated and the pre-burn gas sample was drawn into the cooling / condensing changer and held for 2-3 minutes.

The gas sample was then transferred to the glass sample bulb.

The mixing f an was stopped for approximnely two minutes.

The glow plug was energized.

The post-burn gas was sampled in the same manner as pre-viously described.

The pre-burn and post-burn gas samples were analized by laboratories having gas chromotography capability.

Gases from FENWAL INCORPORATED : ASHLAND MASSACHUSETTS

0. s.oa of wareer Kidde & Compeay, Inc.

5-37

s REpor: No.

PS R-914 PROCEDURE (Cont ' d) tests No. 1 through test No. 5 were analized by:

Arnold Green Testing Labs Inc.

6 Huron Drive Natick, Massachusetts Gases from tests No. 6 through test No. 14 were analized by:

Dynatech R/D Company 99 Erie Street Cambridge, Massachusetts f

=

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS Dives.on of Waiter K;dde & Cepony, Inc.

5-38

• - ~ ~ ~

1 TABl.F. NO. I TAMill.ATFil RF.Sl!LTS T3 T,

Tian.

IP AP Mp Np op lia No U.s Test Tv V

Baro R/M T nah P sir PM

Pit, T

T2 (s'm/Mee 1 No.

H

(*F) (Ft/Ser) (andts) (1)

(*F)

(senHg) (aunHg) (numHg) (*F)(*F) ("F) (*F)

(Ser) (Sec) (psi)

I 12 180 0

763.7 53 70 830.6 183.3 0

230 395 220 1050 14.50 0.50 $3.00 14.0 70.00 18.0 0.0 R 2. e.

17.1 e.s.s l 2

8 180 0

763.7 46 76 830.6 72.2 0

310 330 500

'80 14.00 4.00 33.00 5.80 76.0 20.0 0.0 80.7 IA.R 17.14 3

8 180 0

757.3 78 61 A97.5 78.1 0

245 140 205 190 14.25 4.70 3.00 7.3 74.2 10.4 4.9 76.3 19.I 2e. 04 4

4 12 129 0

763.9 82 55 833.1 128.9 101.6 280 205 l7n 748 15.75 0.55 66.00 8.5 71.4 14.7 0.0 81.1 15.6 e.4.in 5

8 13R 0

763.9 68 50 846.0 85.9 141.7 129 150 150 222 18.25 18.25 22.60 6.5 74.1 19.5 1.6 no.7 17.6 6

12 176 0

759.4 95 67 848.7 165.4 324.2 270 250 228 1000 17.8 0.656 72.00 15.1 62.6 17.9 0.0 n2.6 14.4 51.6n 7

8 190 0

761.9 65 72 900.2 110.6 371.2 218 195 200 657 18.5 68.125 16.25 9.5 73.1 16.9 4.9 79.5 14.4 8

12 145 5

767.2 88 56 836.8 129.3 Ill.7 255 200 200 1000 19.06 0.375 67.50 14.7 61.1 18.9 0.0 85,4 12.6 78.4 5 9

12 130 10 767.2 63 75 R36.R 129.3 lit.7 212 195 175 1000 59.25 0.500 65.00 11.6 62.C 18.0 0.0 76.9 11.9 as in 10 10 146 10 761.1 85 71 A41.6 109.0 142.0 247 200 190 29.0 0.875 53.7-9.6 61.1 IR.6 0.0 16.5 15.2 46.77 C]) 18 to 146 5

761.1 60 81 R48.6 109.0 142.0 242 196 lin 800 23.90 0.781 52.7 10.2 62.6 18.9 0.0 74.7 is.o 47.%6

>2 12 350 in 757.0 85 78 i n5.5 i65.i 75.0 u8 403 395 i000 25.90 o.400 5R.75 ii.i 6a.8 in.0 0.0 ai.4 i e.. o

w.. n Cdi) 13 12 110 0

756.4 47 88 1135.5 165.1 75.0 450 402 400 495 12.06 0.406 60.00 12.0 63.9 16.7 0.0 90.6 12.5 Int.6s

@5D 14 8 350 0

752.5 76 78 1828.8 109.4 129.8 40A 360 370 390 12.00 9.000 30.00 9.3 68.0 IR.7 0.0 71.A 17.9 4.09 t

h h

y 6d D

b

Report No.

PS R-914 Legend for Table No. 1

%H Hydrogen Test Concentration (%)

2 Tv Vessel Test Temperature (OF)

Air Velocity At Glow Pub (Ft/S ec)

V Barometric Pressure (mmHg)

Baro R/H Relative Humidity (%)

Ambient Temperature (UF)

T amb Partial Pressure (mmHg) Of Air Loaded P air Partial Pressure (mmHg) of Hydrogen Loaded PH 2

PHO

' Partial Pressure (mmHg) of Steam Loaded 2

T Glow Plug Box External Wall Maximum Temperature ( F) y T

Vessel Internal Wall Maximum Temperature ( F) 2 f

Glow Plug Box Internal Maximum Temperature ( F) 3 T

Vessel Air Maximum Temperature ( F) 4 Tign Time From Energizing Glow Plug to Ignition (S ec)

Tp Time From Ignition to Maximum Pressure (S ec) 8P Maximum Pressure Increase (psi)

Pre-burn Hydrogen Concentration (%)

Hp Pre-burn Nitrogen Cancentration (%)

Np Pre-burn Oxygen Concentration (%)

Op Post-burn Hydrcgen Concentration (%)

Ha Na Post-burn Nitrogen Ccacentration (%)

Post-burn Oxygen Csncentration (%)

Oa Burning Velocity (Cm/Sec)

Su FENWAL INCORPCRATED : ASHLAND, MASSACHUSETTS Omoon of Walter Kidde & Company, lac.

U$

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PRESSURE fTRANSOUCER r

5 MERCURY

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RECORDING NOME M OSCILLOGRAPil gulCATING TEMPERATURE 2-

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GLOW PLUG BOX 5

WALL 111ERM0 COUPLE i

GLOW PLUG B0X c

MERCURY fn VESSEL WALL THERM 0 COUPLE MANOMETER

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VESSEL WALL /

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VACUUM CONTROL SW l

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STEAM SAMPLE BULB SUPPLY

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COOLING /CONDENSit!G CilAMBER M

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~

5.4 Fenwal Pnase 2 Test Report DETERMINATION OF IGNITION PERFORMANCE CHARACTERISTICS OF A GLOW PLUG HYDROGEN IGNITOR AND THE EFFECT OF EXPOSURE OF EQUIPMENT TO HYDROGEN BURNS FOR WESTINGHOUSE ELECTRIC CORPORATION PITTSBURGH, PENNSYLVANIA REPORT NO. PSR-918 Issued: December 3, 1980

,!)[bc -

id

,4Y[

Prepared by:

p Warner G. Dalzell Test Engineering Supervisor Protection Systems Division Approved by:

,E -

///

fJo'seph Gillis

JIanager xplosion Protection Systems Protec lon Systems Division

/

l FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS l

D.ms.on of Wa:eer Kidde & Cepeny, Inc.

5-39

I

_.__-.z..._......_.

1 s.

Report No.

f PS R-918 i

i

(

SUMMARY

Part 1:

A series of tests was conducted to determine the burning characteristics of various mixtures of hydrogen, air and steam when ignited by a special glow plug ignitor.

These tests were directed to low hydrogen mixtures, and mixtures with 40% steam.

Part 2:

A series of tests was conducted to determine the charact-eristics of the burning which occurs when hydrogen is introduced into a test vessel at a constant rate and when both hydrogen and steam are simultaneously introduced into the test vessel at a constant rate in the presence of an activated glow plug ignitor.

c Part 3:

l A series of tests was conducted to determine the effect of water spray on glow plug ignitor parformance under various j

conditions.

Part 4:

9 A series of tests was conducted to determine the ability of various pieces of equipment to withstand exposure to a hydro-gen burn.

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS Dw;s.on of Waft.r Kidde & Company, Inc I-49

0 Report No.

PS R-918 RESULTS Part 1:

Test H

V AP 2

No.

(%)

(Ft/Sec)

(Psi) 1 9

0 38 2

8 0

3.1 3

7 0

1.5 4

6 0

1.0 5

5 0

0.2 6

8 5

36 7

6 5

15 8

10 0

30 9

6 0/5*

.75/2.7 10 6

0/5*

.2/3.2 Detailed results are shown in Table No.1.

In tests 9 and 10 the draft fan was energized after a period of time.

l FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS l

O wis.on of Waher Kidde & Company. Inc.

5-41

.-.-v.

y y

Report No.

i PS R-918 e

RESULTS Part 2:

Test Hydrogen Steam 21P No.

Added Added (Psi) 1 Yes No 6.1 2*

Yes No 7.8 3**

Yes Yes 10.1 Test 2 was a repeat of test 1 in which a leak in the hydrogen supply line occurred.

Detailed results are shown in Table No.

2.

During the 15 minute test period there were two burns.

One peaked approximately 100 seconds after flow was ini-tiated and the other 618. seconds later.

The first peak 3.6 psi.

7.8 psi and the second a fiP reached a lip

=

=

During the 15 minute test period, there were 8 burns.

The fir st peaked approximately 88 seconds after flow was ini-tiated and the last 350 seconds later.

The first peak 8.9 psi and the last a fiP 10.0 psi.

reached a AP

=

=

The greatest pressure peak was 12.0 psi at the 5th peak.

(333 sec.).

\\

i l

l FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS 0.w.s on of waher K;dde & Company, lac 5-42

Report No.

PS R-918 RESULTS Part 3:

Test H

Hydrogen Water Ignitor Tign AP 2

No.

(%)

Flow Flow Orientation (S ec)

(Psi)

(Initial)

(SCFM)

(GPM) 1 10 0

2 Normal 14.8 60 2

10 0

2 Normal 11.4 50 3

6 0

2 Normal 22.0 32 4

0 4

2 Normal 90,0 3.1 5

10 0

2 Rotated 14.0 42.5 Detailed results are shown in Table No. 3.

Test 2 was a repeat of test 1 in which a leak in the vessel drain valve occurred.

i 1

I W

l FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS 1

D.vis en of we'rer K;dde & Company, Inc.

l

e Report No.

PS R-918 1

RESULTS Part 4:

Test H

Igniter Tign AP 2

No.

(%)

Voltage (S ec)

(Psi) 1 12 12 VAC 27.1 60 2

12 12 VAC 26.8 58 3

12 12 VAC 25.8 63 4

12 12 VAC 26.3 58 5

10 12 VAC 27.6 49 6

10 10 v>C 56.0 50 7

12 12 VAC 27.2 61 Detailed results are shown in Table No. 4.

These tests included typical equipment pre-sent in a containment.

In test 2 a space blanket was used as a component insulator and failed.

The test was repeated in Test 7 using aluminium foil as an insulator.

,~e l

l l

l 9

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS l

o,...on of mire, K;dde & Company, lac-5-44

H l

Report No.

j PS R-918 l

APPARATUS l

Tests were conducted in a 1000 gallon spherical test vessel having a pressure rating of 500 psig with the capability of being heated to 350 F.

The vessel is constructed of carbon steel with a stainless steel liner.

The outside surf ace of the vessel was insulated with 3 inch I

thick fiberglass insulation.

This insulation had an aluminum l

foil face which oriented away from vessel.

Mixing of the various gaseous components was accomplished by means of a small shaded pole electric motor fan.

This fan had a 4 inch diameter blade with an air moving capacity of 200 CFM.

Steam was supplied to the test vessel from an electrically heated boiler which was self-regulated to maintain a pressure of 40-50 psig.

A manually operated ball valve was positioned between the boiler and the test vessel.

The temperature of the test vessel was controlled by a thermocouple controller which had its sensing element in a well inside the vessel and approximately 18 inches from the vessel wall.

The temperature of the test vessel was sensed and recorded from a thermocouple which was approximately 12 inches below the geometric center of the vessel.

~

Hydrogen for the transient tests was supplied from a high pressure supply cylinder, through a regulator, control valve, flowmeter, check valve and then to the bottom of the vessel through a length of 1/4 inch copper tube.

ww FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS Div.s.on of Wa?ser K;dde & Company. Inc.

5-45

~

~

l Report fic.

PS R-918 APPARATUS (Cont'd)

Steam for the transient tests was supplied from the boiler described, through a check valve then to a pipe " tee" where it was mixed with the hydrogen flow.

The mixture of hydrogen'and steam was directed to the bottom of the vessel through a length of 1/4 inch copper tube inside the vessel.

A calibration test of this steam supply indicated the rate to be approximately 0.3 pounds per minute.

Water for the spray tests was supplied from a positive displacement pump which produced the required volume of water through the nozzle.

A sketch of the test apparatus is shown in Figure No. 1.

N u nsu e FENWAL INCORPORATED : ASF: LAND, MASSACHUSETTS o m.on on w.n., riaa. s co ap.ay, i"'

5-%

s Report No.

PS R-918 PROCEDURE Part 1:

Vessel temperature was stabilized at the specified test temperature.

Barometric pressure, relative humidity and ambient temper-ature were read and recorded.

Air, hydrogen and steam (when specified) were added accord-ing to the appropriate partial pressure.

The gas sampling apparatus was evacuated and the p.re-burn gas sample was drawn into the cooling / condensing changer and 4

held for 2-3 minutes.

The gas sample was then transferred to the glass sample bulb which also had been evacuated.

The niixing f an was stopped for approximately two minutes.

The glow plug was energized.

The post-burn gas was sampled in the same m.anner as pre-viously described.

The pre-burn and post-burn gas samples were analized by:

Dynatech R/D Company 99 Erie Street Cambridge, Massachusetts l

_ps4 D h I','.t19 FENWAL INCORPORATED : ASHLAND. MASSACHUSETTS D. mica of walree Kidde & Compeay Inc.

5-47

i Report No.

PS R-918 i

PROCEDURE Part 2:

Vessel temperature was stabilized at the specified test temperature.

Barometric pressure, relative humidity and ambient temper-ature were read and recorded.

The glow plug was energized and allowed to come to a stable temperature.

Hydrogen or steam and hydrogen flow was initiated at the specified flow rate and continued for 15 minutes.

The gas sampling apparatus was evacuated and the gas sample was drawn into the cooling / condensing changer and held for 2-3 minutes.

The gas sample was then transferred to the glass sample bulb which also had been evacuated.

The gas sample was analized by:

Dynatech R/D Company 99 Erie Street Cambridge, Massachusetts e

-= gr_h s

ll { '/~[

w FENWAL INCORPORATED : ASHLAND, MA3SACHUSETTS Dins.on of Walter Kidde & Company, Inc.

pg

O Report No.

PS R-918 PROCEDURE Part 3:

Vessel temperature was stabilized at the specified test temperature.

Baremetric pressure, relative humidity and ambient temper-ature were read and recorded.

Hydrogen, when specified, was added according to the ap-propriate partial pressure.

The vessel contents were mixed for approximately five minutes.

The gas sampling apparatun was evacuated and the pre-burn gas sample was drawn into the cooling / condensing. changer and held for 2-3 minutes.

The gas sample was then transferred to the glass sample bulb.

The mixing fan was stopped for approximately two minutes.

Spray water flow, as specified, was initiated.

Hydrogen flow, when specified, was initiated and continued for 15 minutes.

The glow plug was energized.

The post-burn gas was sampled in the same manner as pre -

viously described.

The pre-burn and post-burn gas samples were analized by:

~

Dyaatech R/D Company 99 Erie Street Cambridge, Massachusetts l

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS l

Div,s;on of Waher K;dde & Company, lac.

5-49

Report No.

PS R-918 PROCEDURE Part 4:

The " Duke" ignitor box was substituted for the "TVA" ignitor box.

The appropriate pieces of equipment to be exposed to the hydrogen burn (see listing) were placed in the vessel and in-strumented v?.th thermocouples as directed.

Vessel temperature was stabilized at the specified test temperature.

Barometric pressure, relative humidity and ambient temper-ature were read and recorded.

Air, hydrogen and steam (when specified) were added accord-ing to the appropriate partial pressure.

The vessel contents were mixed for approximately five min-utes.

The gas sampling apparatus was evacuated and the pre-burn gas sample was drawn into the cooling / condensing changer and held for 2-3 minutes.

The gas sample was then transferred to the glass sample bulb.

The mixing fan was stopped for approximately two minutes.

The glow plug was energized.

l The post-burn gas was sampled in the same manner as pre-viously described.

The pre-burn and post-burn gas samples were analized by:

1 l

Dynatech R/D Company 99 Erie Street i

Cambridge, Massachusetts 4

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS o.~oa or w.n., xida. a comp.ay, iac-5-50

L _.

Report No.

PS R-918 LISTING OF EXPOSED MATERIALS Exposure Description Test No.

Barton Transmitter 2-4-1 2-4-2 2-4-3 2-4-4 2-4-7 ASCO Valve 2-4-3 2-4-4 2-4-7 Namco Switch 2-4-3 2-4-4 2-4-7 Sample Blocks - All 2-4-1 Sample Slabs - All 2-4-2 Fisher Regulator 2-4-7 I

l

~-

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS Diesion of Walter Kidde & C&ny, I" 5-51

o Report No.

PS R-918 LISTING OF EXPOSED MATERIALS (Cont'd) l l

Exposure Wire Description Test No.

WVA 2/C

1. 16 87232 XPS 2-4-2 Type SIS WJH 2-4-2 WVC 2-4-2 WRO SROJJ 2-4-2 s

WVA-1 2/C

1. 18 87232 XPS 2-4-3 WPA - SROAJ 2-4-2 WPD - SROAJ 2-4-2 WPF -

1/C 46 SROAJ 2-4-3 WUB-1 Type TX 2-4-2 WNB - 8KV 2-4-1 Duke - BX 2-4-1 Type CPJ - WDB 2-4-3 RTD 2-4-2 e,

l h4iWtb S

ne-FEfiWAL INCORPORATED : ASHLAND, MASSACHUSETTS 5-52 Divis.on of Walter Kid.ie & Company, Inc.

Report No.

PS R-918 TABLE NO. 1 SERIES 2 - PART 1 Test No.

2-1-1 2-1-2 2-1-3 2-1-4 2-1-5 2-1-6 2-1-7 ; 2-1-8 2-1-9 2-1-10 Date 10/10 10/14 10/14 10/15 10/15 10/15 10/16 10/17 10/17 10/27

%H 9

8 7

6 5

8 6

10 6

6 2

TV F

136 138 140 142 144 138 142 212 212 212 0

0/5 0/5 V

ft/sec 0

0 0

0 0

5 5

~

Baro mmHg 765.3 761.4 761.4 767.7 767.7 767.7 768 767 767 762 R.H.

36 76 35 80 43 34 60 74 55 52 Tamb F

56 41 55 44 51 49 67 65 65 50 Air mmHg 839 843 846 856 858 850 856 535 578 578 H

mmHg 96 86 75 65 54 86 65 107 64 64 2

HO mmHg 134 142 147 157 165 142 157 428 428 428 2

T F

210 141 140 142 144 230 190 280 210/225 212/225 y

T F

175 130 135 142 144 183 152 242 200/220 210/247 2

T F

142 140 140

• 142 144 N.O.

N.O.

240 N.O.

227/289 3

T F

960 165 N.O.

142 144 685 335 700 245 205/208 4

Tign sec 15.8 15.9 15.4 17 17 15 17 17 17/1.0* 19/6.1*

Tp sec 6.6 5.4 5.3 11 3

4 9

9.6 13/10 1.9/4.8

[h P psig 38 3.1 1.5 1.0 0.2 36 15 30

.75/2.7 0.2/3.2

[

H2(P) 9.2 8.8 9.0 8.0 6.4 9.6 6.8 17.9 11.5 6.1 N2(P) 69.6 69.9 69.3 68.6 74.5 72.2 72.9 66.4 71.7 73.7 O2(P) 21.9 21.9 21.8 21.8 22.6 21.6 19.0 16.9 17.9 19.3 H2 (A) 0 3.3 4.5 6.2 5.1 0

3.6 0

9.2 6.1 N2 (A) 78.5 75.8 74.7 71.9 75.0 82.9 75..

85.4 74.3 73.9 02(A) 18.9 20.3 20.6 21.8 22.5 19.6 18.0 12.6 17.8 18.3 N.O.

Not Obtained Timed From Pan Start

Report No.

PS R-918 TABLE NO. 2 SERIES 2 - PART 2 Test No.

2-2-1 2-2-2 2-2-3 Date 10/28 10/29 10/30 TV F

80 80 160 Baro mmHg 759 762 769 R.H.

95 65 57 Tamb F

34 34 37 H

SCFM 4

4 4

2 H O **

lb/ min 0

0 cs. 3 2

T F

215 226 265 y

T F

120 130 190 2

T F

193 198 240 3

T F

318 330 370 4

Tign***

sec 65 100 84 1p sec 12 12 4

b_ P psig 6.1 7.8 10.1 max 23.6 23.9 H2(A) 72.2 71.0 N2(A) 4.8 7.3 02(A)

Hydrogen Flow Rate Steam Flov Rate Approximate Time From Hydrogen Flow Start To First Ignition

(

5

-w

.,s FENWAL INCORPORATED : ASHI AND, MASSACHUSETTS Division of veber Kidde & Cornpeny, Inc.

c Report No.

PS R-918 TABLE NO. 3 SERIES 2 PART 3 Test No.

2-3-1 2,'

2-3-3 2-3-4 2-3-5 Date 10/23 10/31 10/31 10/31 11/3

%H 10%

10%

6%

N.A 10%

2 TV (UF) 39 80 80 80 80 l

Baro (mmHg) 772 760 756 756 771 l

R.H.

(%)

45 50 34 50 50 Tamb

( F) 39 47 48 50 40 H

(mmHg) 86 84 48 0

86 2

H (SCFM) 0 0

0 4

0 2

H 0**

(gal / min) 2 2

2 2

2 2

T F

125

135 80 135 120 y

T F

110 130 120 100 120 2

T F

40 N.G.

133 155 145 3

T F

665

==650 407 505 360 4

Tign sec 14.8 11.4 22.0 90 14.9 Tp sec

.50

.65 1.50 6.0 1.1 Lh P psig 60 50 32 3.1 42.5 Ignitor Orientation Normal Normal Normal Normal Rotated H2 (P)

N.O.

6.7 N.O.

N.O.

7.8 N2(P)

N.O.

73.1 N.O.

N.O.

73.5 02(P)

N.O.

19.4 N.O.

N.O.

19.3 l

H2(A)

N.O.

.8 N.O.

N.O.

O N2(A)

N.O.

79.4 N.O.

N.O. -

8 2 '. 5 ' '

02(A)

N.O.

16.6 N.O.

N.O.

17.5 Hydrogen Flow Rate Water Spray Flow Rate l

N.O. Not Obtained C

We _. --

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS D.v s.on of Walter Kidde & Cepany, Inc.

..--n-.

Report No.

PS R-918 TABLE NO. 4 SERIES 2 - PART 4 Date 11/12 11/13 11/14 11/17 11/16 11/07 11/18 Test No.

2-4-1 2-4-2 2-4-3 2-4-4 2-4-5 2-4-6 2-4-7

%H 12%

12%

12%

12%

10%

10%

12%

2 TV F

129 129 129 129 146 146 129 Baro mmHg 756.6 762.3 755.0 771.0 760.0 754.1 751.6 R.H.

55%

42%

30%

57%

60%

55%

93%

Tamb F

40 37 55 29 39 65 26 Air mmHg 830.3 830.3 830.3 830.3 841.6 841.6 830.3 Hg mmHg 124.1 124.1 124.1 124.1 109.0 109.0 124.1 MO mmHg 111.7 111.7 111.7 111.7 147.0 142.0 111.7 2

i 380 510 T

F y

T F

255 395 365 395 432 510 357 2

202 195 T

F 3

T F

710 760 760 755 790 760 i

735 4

130 T

F 140 140 5

140 T

F 150 155 6

133 T

F 135 140 7

143 T

F 230 250 g

240 250 T

F 9

170 138 T

F 10 240 250 T

F yy 228 183 T

F 12 9

Raport No.

PSR-918

)

TABLE NO. 4 (Cont'd)

SERIES 2 - PART 4 (Cont'd) t i

d l

Date 11/12 11/13 11/14 11/17 11/16 11/07 11/18 i

Test No.

2-4-1 2-4-2 2-4-3 2-4-4 2-4-5 2-4-6 2-4-7 1

.l Volta 12 12 12 12 12 10 12 Space

.0010

.0010 INS None Wrap None Aluminium None None Aluminium Tign Sec 27.1 26.8 25.8 26.3 27.6 56.0 27.2

. 6 '4

.70

.55

.65 1.750 1.500

.60 Tp sec

[i P psig 60 psig 58 psig 63 psig 58 psig 49 psig 50 psig 61 psig H2(P) %

13.1 12.8 14.1 13.6 9.3 9.8 10.6 N2(P) %

68.8 69.4 68.1 69.0 74.4 70.9 73.3 02(P) %

18.0 18.0 17.7 18.2 18.7 18.4 18.8 H2(A) %

0 0

0 0

0 0

0 N2 (a) %

83.7 83.7 83.1 84.9 82.9 81.0 83.7 02(A) %

15.0 14.5 14.8 15.6 15.8 15.4 14.9 4

.,::= - ~. :.1:.* : ~... :..

I

.~.

Report No.

PS R-918 Legend For Table No. 1, No. 2, No. 3 and No. 4 Hydrogen Test Concentration (%)

%H 2

Vessel Test Temperature (UF) l TV Air Velocity At Glow Plug (f t/sec)

V Barometric Pressure (mmHg)

Baro Relative Humidity (%)

R. H.

Ambient Temperature ( F)

T amb Partial Pressure (mmHg) Of Air Loaded P air Partial Pressure (mmHg) Of Hydrogen Loaded PH 2

Partial Pressure (mmHg) Of Steam Loaded PHO 2

Glow Plug Box External Wall Maxiumu Temperature (UF)

T y

Vessel Internal Wall Maximum Temperature (#F)

T 2

T G1 w Plug Box Internal Gas Maximum Temperature ( F) 3 Vessel Air Maximum Temperature ( F)

T 4

Barton Transmitter 2 2 ( F)

T S

~

Barton Transmitter t 4 (OF)

T 6

Barton Transmitter T 5 -( F)

T 7

Barton Transmitter - Outside Surface Maximum Temperature T

8 o) p Limit Switch - Outside Surf ace Maximum Temperature T

g

( F)

Limit Switch - Internal Maximum Temperature ( F) 7 10 T

Solenoid Valve - Outside Surface Maximum Temperature yy (OF)

T S len id Valve - Internal Maximum Temperature ( F) 12 Voltage At Glow Plug (VAC)

Volts Insulating Wrap Type INS l

FENWAL INCORPORATED : ASHLAND, MASSACHUSETTS Devson of Walter Kidde & Company, lac.

e i

Report No.

PS R-918

{

Legend (Cont'd)

Time From Energizing Glow Plug To Ignition (sec)

Tign Time From Ignition To Maximum Pressure (sec)

Tp bP Maximum Explosion Pressure Increase (psi)

Pre-burn Hydrogen Concentration (%)

Hp Np Pre-burn Nitrogen Concentration (%)

Pre-burn Oxygen Concentration (%)

Op Post-burn Hydrogen Ccmcentration (%)

Ha Post-burn Nitrogen Concentration (%)

Na Post-burn Oxygen Concentration (%)

Oa

~

(-

'M FENWAL INCORPORATED : ASHLAND. MASSACHUSETTS D. vision of Weiter Kidde & Company, Inc.

e Report No.

PS R-918 SPMY N0ZZLE WTTER PUMP PRESSURE I RANSDUCER (2)

T HERCURY RECORDING i

mat:071ETER INDICATING TE!4PERATURE C0'4 TROLLER CONTROLLER V

,#THERl10C00PLE 2

GLOW PLUG 60X GLOW FLUG E0X t!All. TEf1P, REC 5

\\

/

TD1PERATURE R CORDER GLOW PLUG BOX

\\/

WALL THERMOCOUPLE CLOW PLUG BOX

'THERN0 COUPLE l'ERCURY VESSEL WALL IIK:0:4ETER __

~

THERi40 COUPLE GLOW PLUG R

lv f

o AIR FLOW VESSEL U11.L FA!J

+

4 e-C TG4P. REC, e

c-g i

GLOW PLUG CI:ECK GLOW PLUG VESSEL TEtP THERM 0COUPLS VACUtH

]

CONTROL SW M

VALVE PUMP F GAS MIXING STEAM

--@-1 FAf1 SAMPLE BULB r%

SUPPLY SAf4PLE p

Ci'ECK p

VESSEL f

VlLVE C00LIEG/C0!1DEtiSillG QHVDROGEf1 TENP. REC.

CHAfDER SUPPLY FL0tlMETER VESSEL DRAlf1

.