ML19317F249

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Forwards Addl Info on Containment Pressure Time Response for Various Postulated Design Basis LOCAs Per AEC 721025 Request
ML19317F249
Person / Time
Site: Oconee  
Issue date: 12/19/1972
From: Thies A
DUKE POWER CO.
To: Schwencer A
US ATOMIC ENERGY COMMISSION (AEC)
References
NUDOCS 8001090588
Download: ML19317F249 (1)
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s s I'. O. Dv t a. 7 9 s. s. Y g e e s ne s % + es2 % .ber9es er e. g a, e., s December 19, 1972 ?!r. Al Schwencer, Chief Pressurl:ed Water Reactors Leanch 4 Dir ctorate of licensing U. ,, tonic Energy Commission Washington, D. C. 20545 Re: Oconee Nuclear Station Docket Nos. 50-270 and -287

Dear Mr..Schwencer:

In response to your letter of October 25, 1972, please find attached additional information concerning containment pressure time response for various postulated design basis loss-of-coolant accidents. Please advi a if you desire additional information. Very truly yours, f WJ~ A. C. Thies j i ACT/v \\ \\ \\ " 9 0 S@> ?f

r Attachecnt to A. C. Thiss' Larter Dated December 19, 1972 i." OCONEE NUCLEAR STATION UNITS 2 AND 3 AEC REQUEST FOR ADDITIONAL INFORMATION 14.0 SAFETY ANALYSIS, The reactor building pressure-time response is shown in the FSAR for a spectrum of breaks in the hot leg piping after it was determined that breass in the hot leg resulted in the highest building pressures. The assumptions used for that analysis are also given the FSAR, Mass and energy release rates from the reactor coolant system were determined by the use of the 3-region FLASH code. The revised analysis presented here utilized mass and energy release rates determined by the use of a =ultiregion CRAFT code. The nodal arrange =ent of the CRAFT codel is shown on Figure 14-1. The secondary side of the steam generators and the associated feedwater piping are represented by control volumes 6, 20, 7, and 21. Main feedwater was added directly into the secondary side of the steam generators over a period of 17 seconds as the feedwater control valve closed. At 15 seconds, the paths connecting the feedwater piping to the steam generators (which were assumed to be closed in the CRAFT model until this time) were opened so that the = ass and energy trapped in the piping could enter the steam generator. Auxiliary feedwater started at approximately 35 seconds. Sensible heat stored in the steam generator tubes was modeled by slabs of metal in the secondary control volumes. Stored heat in the primary =etal was sinulated by slabs of metal in the control volumes which discharge their stored energy as the reactor coolant system te=perature decreases. To ensure a conservative calculation, the CRAFT code was run at 102% core power (2619 MWt) and the code of heat transfer in the core was assumed to be nucleate boiling until the quality of the coolant was approximately 1.0. Decay heat was calculated by using the ANS Standard ti=es 1.2. The entire transient (blowdown and reflood periods) was siculated using the CRAFT code. In order to present a conservative analysis for the reactor building pressure response, it was assumed that the single failure was a power failure which resulted in minimum reactor building cooling (2 coolers and 1 spray). The coolers were assumed to be operative in 25 seconds and sprays started at 75 seconds. Thissamefailureallowsoperationofonly1HPIand1(LPIpump. To see the effect of this assumption on the contain=ent pressure, runs were made using 2 LPI pu=ps. A negligible difference in pressure was seen. As in the FSAR analysis, the highest building pressure occurred for a hot leg break. The highest pressure (53.5 psig) was obtained for the largest break 2 (14.1 ft ). These hot leg breaks resulted in removing heat from the steam generators because of the backflow of emergency coolant through the steam generators. Figure 14-2 through 14-5 show the pressure time response for 4 hot leg breaks. Breaks in the cold leg piping at the pump suction and the pump discharge were analyzed. It was determined that breaks at the pdmp suction resulted in the higher pressures than those at the pump discharge. Four break sizes at the 2 2 , and 8.55 ft ) were analyzed as well as pump discharge (0.5 f t2, 3 f t, 5.13 ft t-l 14-1 l

r s v % 5 six break sizes at the pu=p suction (0.5 f t2, 2 f t2, 3 ft2, 5.13 ft2, 7 f t2, and 8.55 ft2). Guillotine and split type breaks were studied, but in all cases, splits yielded the higher pressures. The 7.0 ft2 break resulted in the highest pressure of 53.4 psig 'ihich is approximately the same pressure as the worst hot leg break. The pressere ti=e responses for the six suction breaks are shown on Figures 14-6 threu~h 14-11 and the t e breaks are shown on Figures 14-12 through 14-15. Althcugh the prir.,. _ _... 'icu from the core is through the vent valves, the ccendary side energy is r emoved. The effect is obvious in the pressure-ti=e response curves. Table 14-1 shows the peak pressure and the time when the peak occurs for each of the breaks in the hot and cold legs. The core inlet velocity during the reflood stage is oscillatory in nature but, by using the integral of the core inlet flow path, the core average velocity was 2 suction break. The determined and is shown on Figure 14-16 for the 7.0 ft CRAFT code conservatively calculates an average carryout rate fraction of approximately 0.9 of the core inlet flow, Table 14-2 shows the leak flow rate and enthalpy for the 14.1 ft2 hot leg break and Table 14-3 shows the came quantities for the 7.0 ft2 cold leg break at the pump suction. As can be seen from Table 14-3, the leak flow was zero fren 36 to 40 seconds and again from 44 to 48 seconds which is caused by the building pressure, as calcr2ated by CRAFT, coming into eq tilibrium with RCS pressure. To show that the input is still conservative, Figure 14-17 shows the comparison-betweer. the building pressure calculated by CRAFT and CONTEMPT. As can be seen from this figure, the CONTEMPT pressure is higher during the first 200 seconds than the CRAFT pressure which i= plies that zero' leak flow would have occurred ear 11er. In order to provide a better understanding of where the energy came from, Table 14-4 shows an energy balance at t = 0 sec., and at the time of peak pressure at t = 120 sec. for the 7 ft2 cold leg break at the pump suction. Energy added by the core, steam generators ICCS, and building cooling systems is also shown. The reference temperature for these calculations was 32 F with the exception of the reactor building structures where the initial building temperature of 110 F was used. As can be seen from this table and Figure 14-7, all of the available energy sources have contributed substantially to the reactor building pressure response and considerable margin still remains be-tween the peak building pressure and building design pressure. c. ~* i. e s# 9 9 14-2

i It s LIST OF TABLES Table Title Pace 14-1 Peak Reactor Building Pressure Versus Break Area and Location 14-2 Mass Rate and Enthalpy to the Reactor Building for a 14.1 ft2 Hot Leg Break 14-3 Mass Rate and Enthalpy to the Reactor Building for a 7 ft2 Cold Leg Break at the Pump Suction 14-4 Energy Distribution for the 7 ft2 Cold Leg Break at the Pump Suction i i i s 4 i / 9 3 \\ e 9 Ib3 r rv w-g

LIST OF FIGURES j Figure Title Pace 14-1 Multinode Reprcacntation c' '*cclear Stean Supply Systc= 14-2 Reactor Building Pressure Versus Time for a 14.1 ft2 Hot Leg Break 14-3 Reactor Building Pressure Versus Ti=e for 11.0 ft2 Hot Leg Break 14-4 Reactor Building Pressure Versus Time for 8.55 ft2 Hot Leg Break 14-5 Reactor Building Pressure Versus Ti=e for 5.0 ft2 Hot Leg Break 14-6 Reactor Building Pressure Versus Time for a 8.55 ft2 Cold Leg Break (Pu=p Suction) 14-7 Reactor Building Pressure Versus Time for 7.0 ft2 Cold Leg Break (Pu=p Suction) 14-8 Reactor Building Pressure Versus Time for a 5.13 ft2 Cold Leg Break (Pump Suction) Pressure Versus Time for a 3.0 ft2 14-9 ReactorBuildinfPumpSuction) Cold Leg 3reak 2 14-10 Reactor Building Pressure Versus Time for a 2.0 ft Cold Leg Break (Pump Suction) 14-11 Reactor Building Pressure Versus Time for a 0.5 ft2 Cold Leg Break (Pump Suction) 14-12 Reactor Building Pressure Versus Time for a 8.55 ft2 Cold Leg Break (Pump Discharge) ," 14-13 Reactor Building Pressure Versus Time for 5.13 ft 2 / Cold Leg Break (Pump Discharge) i 14-14 Reactor Building Pressure Versus Time for 3.0 ft2 Cold Leg Break (Pump Discharge) 14-15 Reactor Building Pressure Versus Time for 0.5 ft2 Cold Leg Break (Pump Discharge) 14-16 Average Core Inlet Velocity Versus Time for a 7 ft2 Cold Leg Break (Pump Suction) 14-17 Comparison of CRAFT AND CONTDIPT Reactor Building Pressures 14-4

n TABLE 14-1 i PEAK REACTOR BliTT.DI"G PRESSL*RE VERSUS EREAK AREA A"D LOCATIO'i Ares, e -2 L c t' m Tira of Peak, see ~ 14.1 Hot Leg 53.5 94 11.0 Hot Leg 53.3 100 8.55 Hot Leg 52.9 100 5 Hot Leg 52.7 140 8.55 Cold Leg (Pump Suction) 52.3 120 7 Cold Leg (Pump Suction) 53.4 120 5.13 Cold Leg (Pump Suction) 52.6 140 3 Cold Leg (Pump Suction) 50.0 160 2 Cold Leg (Pump Suction) 49.1 (1st Peak) 76 48.7 (2nd Peak) 157 .5 Cold Leg (Pump Suction) 41.1 240 8.55 Cold Leg (Pump Discharge) 49.8 21 5.13 Cold Leg (Pump Discharge) 48.5 26 / 3 Cold Leg 1 (Pump Discharge) 47.8 35 .5 Cold Leg (Pump Discharge) 41.1 239 o b

TALLE 14-2 MASS RATE AD E'GiL?Y TO TRE REACTOR BUILDIG FOR A 14.1-?T2 EOT LEC 3REAK Ti=e Average Mass Average Interval Flow Rate Enthalpy (sec) (lb/sec) (Btu /lb) "0-2 30,249.5 599.2 2-4 60,009. 595.1 4-6 46,675.5 601.9 6-8 30,404.5 636.1 8-10 14,993. 736.3 10-12 4,807. 1031.8 12-14

2376, 1181.3 14-16 1636.

1065.7 16-18 1326.5 611.3 18-21 259.33 780.2 21-26 0. 0. 26-30 321.5 269.8 30-34 953. 274.1 34-38 54, 263.8 38-42 546.75 304.5 42-44 168. 857.1 44-46 1540.5 296.9 46-48 2936.5 325.3 48-50 2084. 510.5 50-52 2337.5 459.6 52-54 2419.5 504.2 54-56 2963. 403.4 56-58 3391.5 369.4 58-60 3268.5 395.5 60-70 2938.1 404.8 70-80 2185.1 472.7 80-90 1778.3 510.4 90-100 1387. 420.0 100-120 493.85 ~455.6 120-140 403.65 37643 140-160 366.2 366.'O 160-180 363.75 350.1 180-200 368. 337.0 200-220 370.85 326.2 220-240 365.8 315.3 240-260 397.25 303.0 260-280 482.7 293. 3r 280-300 453.8 290.6 e 14-6 t \\ }

9 TABLE 14-3 MASS RATE A?'D ENTHALPY TO THE REACTOR BUILDI!!G FOR A 7-FTJ SPLIT AT THE PO'? SUCTIC': Ti=e Aterage Mass Average Interval Flow Rate Enthalpy (see) (1b/see) (Btu /lb) 0-2 57300 558.333 2-4 53350 566.382 4-6 47035 583.019 6-8 34195 617.780 8-10 22187 689.503 10-12 12904 765.916 12-14 4768 1086.838 14-16 4630 .735.501 16-18 5605 520.250 18-20 5416 457.903 20-24 2893 419.165 24-28 889 412.658 28-32 14 298.246 32-36 38 337.748 36-40 0.0 0.0 40-44 48 333.333 44-48 0.0 0.0 48-56 79 265.263 56-62 1427 416.472 62-68 656 1073.895 68-74 1477 604.153 74-80 2688 461.519 80-90 2479 477.207 90-100 1959 538.497 100-110 1131 692.002 888.632 110-120 561 r 120-140 157 , 1133.524 140-160 54 1180.801 160-180 50 1182.093 180-200 48 1148.691 200-240 323 431.353 240-280 673 474!770 280-320 556 _438'.506 320-360 340 344.001 360-400 413 322.518 400-440 540 316.633 440-480 391 300.288 480-520 383 280.439 520-560 359 275.384 560-600 345 273.663 14-7

l TABLE 14-4 ENERGY DISTRIBUTION FOR Tile 7_FT2 BREAK (SPLIT) AT REACTOR COOLANT PUMP SUCTION \\ Energy Before Energy Added Energy et Time of Peak Diceription Accident. Btu x 10-6 Between 0 and 120 s Pressure (120 sec). Btu x 10 1. Reactor Coolant 298.17 24.28 System, doolant 2. Reactor Coolant Systems Structures a. Fuel & cladding 22.95 5.89 .b. Vesse1, piping, 157.22 147.31 prem:nr i /.cr and primai v :iide of stenn rynerators 3. Core llent Generation 17.32 4. ECCS Coolant 13.04 5. From Second.iry System 31.03 Including Tubes 6. Reactor lhillding 1.78 245.72 Atmosphere 7. Reactor 1s:ijding Sump 0.0 82.0 8. Reactor BuIIding Structures 0.0 32.89 9. Reactor Building Coolers s - 3.96 10. Reactor Building Sprays .54 480.12 57.97 538.09 9 14-8

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d 60 f~g From CRAFT / 7,, f. 50 N I From CONTEMPT N 40 r a a y 30 a. E 20 3 E 10 0 0 100 200 300 400 500 600 Time, s i COMPARISON OF CRAFT AND COWTEMPT REACTOR BUILDING PRESSURES Figure 14-17

..~..*--. .r- \\ i.. Le s a..L ar 19, 1) T; "r. A. Schwencer, Chief Pressurized Water Reactors, Branch 4 Directorate of Licensing U. S. Atomic Energy Cccmission Washington, D. C. 20545 Re: Ocenee Nuclear Station Docket Nos. 50-270 and -287

Dear Mr. Schwencer:

In response to your letter of November 3, 1972, please find attached additional information concerning peak cladding temperatures using the' CRF codel in the REFLOOD code and hand calculations for a.5 square foot break using the small break analysis method. Please advise if you deaire additional information. Very truly yours, .V e i A. C. Thies ACT:er .\\ttachm:at f.

Attachment to A. C. Thiss' Letter 'Jated December 19, 1972 g\\ OCONEE NUC'. EAR STATICN UNITS 2 AMD 3 AEC REQUEST FOR ADEITIONAL INF0:C:ATION 14.0 SAFETY ANI. LYSIS 14.2 For spectrum of breaks, recompute peak cladding temperature using the CRF model in the REFLOOD code. Include, in addition to usual infor=ation (Tclad, metal-water reaction, etc.), the procedures for calculating h versus tice, after beginning of core recovery. Vary location of axial q max. The evaluation of Babcock and Wilcox's reactor design that uses internal vent ~ valves and have pouer levels up to 2568 MRt during a loss-of-coolang accident 1 2 is reported in BAW-10034, Rev. 3. For that analysis, the REFLOOD code, used by B&W for flooding rate computation, combined FLECHT heat transfer coefficients with a conservative entrain =ent assumption (20%) to determine effluent from the core during reflooding. As an alternate, however, B&W has developed a correlation for the carryout rate fraction using data from the FWR-FLECHT program. This correlation h'as now been used in the REFLOOD program for the spectrum of breaks reported in BAW-10034, Rev. 3, to determine the fraction of core inlet flow that is entrained and/or converted into steam during each loss-of-coolant accident. This change in the reflood codel results in slightly lower flooding rates and minor increases in the calculated maxi =um, hot spot cladding tem-peratures. Table 14.2-1 su=sarizes pertinent paraceters and results for the spectrum of breaks considered, and Figures 14.2-1 through 14.2-30 show the core flooding rate, post-blowdown heat transfer coefficient, and the cladding temperatureresgonseforeachbreakintheorderpresentedinTable14.2-1. For the 8.55 ft split case with a sy==etrical power shape (peak at midplane), the heat transfer coefficient and coolant te=perature during the blowdown period are also shown. All of thc. pertinent parameters related to core cooling for this break and power shape are shown on Figures 14.2-25 through 14.2-30. The REFLOOD code uses a carryout rate fraction that assumes that entrainment of water by the steam does not start until the quench front or water level has reachedanelevationof18inchesinthecoreresultinginaninitia1{high j flooding rate. This carryout rate fraction is described in detail in the redirect and rebuttal testimony filed by B&W on October 26, 1972 at the ECCS l public hearing. A further justification for using 18 inches as the starting point for entrainment can be obtained by examining the axial pressure drop data from the FLECHT tests. These data show that the pressure drop can be l related to the static head of the incoming water until the water level reaches . =24 inches in the bundle. This can be seen for flooding rates ranging'from 1 to 6 inches /sec. 2 Using this correlation for the worst cold leg break, 8.55 ft split at the pump discharge, the =axi=us cladding te=perature increased from 2177F go 2186F. The largast increase in peck cicd te:perature occurred for the 3.0 f t" split in the cold leg pipe at the pump discharge. An increase of 76F in the peak l cladding temperature was calculated when the carryout rate fraction correlation i s ---g

t s 'e based on FLECHT data was used. For this relatively small break, the reflood portion of the transient is restricted sonewhat due to the lack of flow available from the core ficoding tonhs after the quench front reachas 18 inches into the core. Thus, thrc.dng away the CFI vat ar which entered rarc ;r_ ; ion during the blowdown period plus usin; the FL:CHT carryout correlation causes a reduction in flooding rate and heat transfer coefficient which in turn reselts in a higher cladding tc=perature. In addition, the 2 split in a cold leg pipe predicts a low reflood analysis for the 0.5 ft flooding rate,'shown in Figure 14.2-19, shortly after the water reaches the bottom of the core. To conservatively analyze the cladding response during this tine period (81 to 85s), the adiabatic heatup of the fuel was extended until 85 seconds after the end of blowdown. At that eine FLECHT heat transfer coefficients based on a 1 in/s flooding rate were used. To insure that the use of the 1.7 design, axial power shape, which peaks at the 3 foot elevation, is still conservative when the carryout rate fraction correlation is used, the worst cold leg break was analyzed using a 1.67 sy=netrical power shape. Calculations show that the maxi =u= cladding temperature is 2135F. Since the same break produces a cladding temperature of 2186F, 51F higher, when Q=ax is located at the 3.0 foot elevation; the B&W evaluation codel is justifiably conservative in its selection of an inlet, axial power shape. Although the carryout rate fraction correlation has only a slight effect on the peak cladding temperatures, its use does decrease the rate at which the cladding te=perature falls af ter the peak has been reached. This pheno =ena produces an increase in local and core =ctal-vater reaction. In fact, the values shown in Table 14.2-1 are approximately a factor of two greater than those reported in BAR-10034, Rev. 3. This increase is quite significant, but still well within the limitation set forth in the AEC Interim Acceptance Criteria. The heat transfer coefficients used in the reflood portion of the THETA 1-B calcu-lations are computed using the FLECHT correlations for various flooding rates. To end some confusion concerning methods e= ployed by B&W in converting the flooding rates predicted by the REFLOOD code to FLECHT heat transfer coefficients, a detailed explanation of the calculations involved for the worst cold leg break is presented. The 8.55 ft2 split at the pump discharge has been shown to result in the worst hot spot cladding te=perature. For this particular break, the end of blowdown is calculated to be 18.75, and the hot pin is assumed to undergo adiabatic heatup until the water in the vessel reaches the bottom of the core (6.93 seconds later). The instantaneous flooding rate that follows is shown in Figure 14.2-7. The REFLOOD code continually integrates the entering core flow, and the resulting integrated mass is used to deter =ine the uniform (square wave) flooding rates. For Figure 14.2-7, two (square wave) flooding rates are used to calculate the FLECHT heat transfer coefficients. The first is used for the time interval of 6.93s to 10.4s; the flooding rate is fairly high initially because entrain-ment of water is assu=cd to be :cro until the water reaches the 18 inch elevation in the core. The end of the first Laterval (10.4s) is selected at the point d 14.2-2

,c .,s where the flooding rate drops to its lowest value follouing the initiation of entrainment. At 10.4s the total tass injected into the core is calculated to bc 6S95.S2 pounds. To dater =ine the (square wave) ficoding rate the total tass injected into th2 cerc frca 6.93s to 10.4s is converted to an equivalent flooding rate as follows: Flooding Rate = (Total Mass injected) (Seecific Volume of Water) ,(Core Flooding Area) (Ti=e Interval) 3 = (6895.82 lb) (.01726 ft /lb) (12 in/ft) (65.7 fei) (10.4 - 6.93s) = 6.~265 in/s Where the specific volume of water is taken at saturated pressure conditions (49 psia) and the core and the core bypass are con-servatively assumed to flood at the same rate. For the actual heat transfer calculations, a flooding rate of 6.25 in/s is used. For the remainder of the reflooding period, 10.4s to 70s, an additional 35422 l pounds of water are injected into the core. In a like manner, an equivalent l flooding rate of 1.8 in/s is computed. Having established the square wave approxi=ations to the reflood. curve, the heat transfer coefficients for each flooding rate are calculated using the FLECHT correlatica (WCAP-7665)3 Input to the FLECHT correlation is based on the following initial conditions which exist at the~end of the adichatic' heat i { up period: Initial Clav Temperature = 2100F i Pressure = 49 psia Power = 1.7 kw/ft Percent Blockage = 0.0 Inlet Subcooling = 90F i The linear heat rate (1.7 kw/f t) represents the peak power for a symmetrical pcwer ~ shaped curve which matches the axial energy generation profile for the 1.7 inlet peak distribution up to the three foot elevation. Heat transfer / coefficients as a function of time, for input into THETA 1-B are caltulated in a manner similar to that suggested in the PWR-FLECHT Final Report.3 The FLECHT heat transfer correlation is applied for flooding rates of 6.25 in/s ana 1.8 in/s. The former flooding rate is used to determine the heat transfer coefficient during r.he first interval (3.47s). The 6.25 in/s flooding rate for 3.47 see is equivalent to 1.8 in/s for 12 seconds. Therefore, the run made to determine h is entered in at 12 seconds for the 1.8 in/s flooding rate. However, the heat transfer coefficient is always adjusted so that the heat transfer coefficient is always equal to or smaller than that given by a simple excess mass approach. The resulting heat transfer coefficient is shown in Figure 14.2-8. 14.2-3

t 4 REFEPJDICES 1. C. E. Parks, et. al., Multi-:Mdc Analysis of BI',.s 256E.".it ::uclear Pl nts During a Loss-cf-Coolcat Ac:ident, EA':-1C034, Re r. 3, Ea'acock & Wilcox Lynchburg, Va., l'ay, 1972, 2. C. E. Parks and K. C. Shieh, REFLOOD - Description of Model for Multinode Core Reflood Analysis, 3AW-10031, Supplenent 1, Babcock & Wilcox, Lynchburg, Va., April, 1972. 3. F. F. Cader, et. al., PWR FLECHT (Full-Length E=ergency Cooling Heat Transfer) Final Report, WCAP-7665, April, 1971. e - er b e g i l } l ) 4 I 1 l e 14.2-4

j . TABLE 14.2-1 e g

SUMMARY

OF BREAK RESULTS Start of End of Peak Brask Size, CF Tank End of CF Tank Cladding g al-Water Reaction, % 2 ft /Descrip. Break Iocation Injection,s Blowdown,s Injection,s Temp., F Local Core 8.55/ cold leg Pump Discharge 9.3 14.6 39.4 2082 2.11 .073 (Guillotine) 5.13/ cold leg Pump Discharge 12.9 21.5 43.9 2029 1.8 .058 (Guillotine) 8.55/ cold Icg Pump Discharge 11.'1 18.7 41.9 2186 2.98 .09 (Split) ~ Z 5.13/ cold leg ' Pump Discharge 13.8 24.0 44.4 1994 1.8 .056 (S lit) P

n d.

8.55/ cold leg Pump Suction 10.5 21.0 41.8 1899 1.15 .042 (Split) 3.0/ cold leg Pump Discharge 20.3 31.8 51.6 1728 .046 .011 (Split) 0.5/ cold leg Pump Discharge 119 192.5 197.5 1660 0.22 0.0044 (Split) 14.1/ hot leg Reactor Vessel 7.0 16.0 37.8 1670 .14 .003 (Split) Outlet 8.55/ cold leg Pump Discharge' 10.8 19.6 41.4 2135 4.2 .24 (Split-Cosine Peak) ~~ \\ 4 9 7

t ,s LIST OF FIGURES Descristien Figure 2 14.2-1 Core Flooding Rate for 8.55 ft Guillotine Cold Leg Break at Pu:p Discharge 14.2-2 Post Blowdown Hot Spot Heat Transfer Coefficient for 8.55 ft2 Guillotine Cold Leg Break at Pump Discharge 2 14.2-3 Hot Spot Cladding Temperature for 8.55 ft Guillotine Cold Leg Break at Pump Discharge 2 14.2-4 Core Flooding Rate for 5.13 ft Guillotine Cold Leg Break at Pump Discharge PogtBlowdownHotSpotHeatTransferCoefficientfor5.13 14.2-5 ft Guillotine Cold Leg Break at Pu=p Discharge 2 Guillotine Cold 14.2-6 Hot Spot Cladding Temperature for 5.13 ft Leg Break at Pu=p Discharge 2 14.2-7 Core Flooding Rate for 8.55 f t Split in Cold Leg Pipe at Pump Discharge 14.2-8 Post Blowdown Hot Spot Heat Transfer Coefficient for 8.55 ft2 Split in Cold Leg Pipe at Pump Discharge 2 14.2-9 Hot Spot Cladding Temperature for 8.55 ft Split in Cold Leg Pipe at Pu=p Discharge 2 14.2-10 Core Flooding Rate for 5.13 ft Split in Cold Leg Pipe at Pump Discharge 14.2-11 Post Blowdown Hot Spot Heat Transfer Coefficient for 5.13 ft2 Split in Coli Leg Pipe at Pump Discharge 2 14.2-12 Hot Spot Cladding Temperature for 5.13 ft Split in Cold Leg Pipe at Pump Discharge 14.2-13 Core Flooding Rate for 8.55 Split in Cold Leg Pipe at Pump Suction 14.2-14 Post Blowdown Hot Spot Heat Transfer Coefficient for 8.55 ft2 Split in Cold Leg Pipe at Pump Suction 2 14.2-15 Hot Spot Cladding Temperature for 8.55 f t Split in Cold Leg Pipe at Pump Suction 2 14.2-16 Core Flooding Rate for 3.0 ft Split in Cold Leg Pipe at Pump Discharge a 14.2-6 s e

.t t Description Figure Post Blowdown Hot Spot Heat Transfer Coefficient for 3.0 14.2-17 ft2 Split in Cold Leg Pipe at Pu=p Discharge 2 14.2-18 Hot Spot Cladding Te=perature for 3.0 ft Split in Cold Leg Pipe at Pump Discharge 2 14.2-19 Core Flooding Rate for 0.5 ft Split in Cold Leg Pipe at Pump Discharge Post Blowdown Hot Spot Heat Transfer Coefficient for 0.5 14.2-20 ft2 Split in Cold Leg Pipe at Pump Discharge 2 14.2-21 Hot Spot Cladding Temperature for 0.5 ft Split in Cold Leg Pipe at Pump Discharge 14.2-22 Core Flooding Rate for 14.1 ft Hot Leg Break Pogt Blowdown Hot Spot Heat Transfer, Coefficient for 14.1 14.2-23 ft Hot Leg Break 2 14.2-24 Hot Spot Cladding Temperature for 14.1 f t Hot Leg Break 2 14.2-25 Smoothed Hot Spot Mass Flux for 8.55 ft split in Cold Leg Pipe at Pusp Discharge with Sy==etrical Power Shape 2 14.2-26 Hot Spot Heat Transfer Coefficient for 8.55 ft Split in Cold Leg Pipe at Pump Discharge with a Symmetrical Power Shape 2 14.2-27 Hot Spot Fluid Temperature for 8.55 ft Split in Cold Leg Pipe at Pu=p Discharge with a Sy==etrical Power Shape 2 14.2-28 Core Flooding Rate for 8.55 ft Split in Cold Leg Pipe at Pump Discharge vith a Sy= metrical Power Shape 12.2-29 Power Blowdown Hot Spot Heat Transfer Coefficient for 8.55 ft2 Split in Cold Leg Pipe at Pump Discharge wit *. p Symmetrical / Power Shape i ^ 2 14.2-30 Hot Spot Claddine. Temperature for 8.55 ft gp11t in Cold Leg Pipe at Pump Discharge with.a Symmetrical Power Shape 1 S o 14.2-7

.t Flooding Rate, in/s Q N O - l I l 1 I r m m m m ed w m ammm m 1 I I I 6 9 .s' I a / 0 ~ g s e i O k O g O 8 5 3 n I

== = f. 3 I 5 8 r i 1 O O O e r" W l C A P m m r-g Q O l O 03 Q M = m E g '> O ,e M g N g i m O C -Tt E O [ j s N N l i

N O LJB g 2 > M "T9 ll43 =4 N I O o no tO m C c 9 C 4 = r" r* 3 O -4 X m t i l 1

l l i f ( a, =w w 6 E N o = - m =.- w < o o J K .M a< .- o - 6 3 < o. w =~ o w \\ o N W W a. o x a. m o M e a. o = E .= o o, = m w a n u o z m

  • w o

o a v wa a - A > W o S e w .4 o o o

a. u o n

fo Y E o \\ ~m es-o Vb ? R k esg R a o o o o S S g g g d o ~gii ~' % :ll a

  • 4

/ \\ S e s 0 9

a l 9 4 1 W O S 4 M. p M M 8 b.4 e en U , W== E en. H. s S 4 e e a. 9 W e. =O O E 4A. 3 b a S Oh W M >= 3 4 t= 4 W 8 a 4 l tee led S. E / 3 5" -=* / l*-/ ea aee O e d O O $/ 4 U .J o U W n W B-8" / O. 4 O d ame >=== 3 O g 9 82 e.l Ie - r 9 a. A. \\. ~* eo y e S 9 D +** o o g R E 0 e o g R -8 n e J.*emuecaer viarvis 1 t e s [ e e u p*** - e -e.-.....~

W W g 3 N oW

P J C g

J K g = 4 = g N D E b C U D 84 9 N I H Q W 6 L E9 % I - D e b W >= O a:: 4 i OE nd 4 taJ haJ I >= K 4 W E O O O haJ E J I 4 O O gun O J l C O g J U b (W O O E 8 4x2 W 1 a N Il g 2 a= a l 12 = = i .E l O s 1 = t I O I ._ _ _ _ _ _..J_. O 3 i .e** O eo no W N O N .O l m /ui *nen suipoota 1 / \\ D e

= m w w i 6 E N = - o a r w er = = o o M .J K r .a e - z u r o o = 4 o e a wzu o w r r % L o o x N a. F3 D l' m - 6 r e r o = x aeo = = m < e x w = o = o = m x w o.- o J U w a e m - b r m o m w a o o o g n. u o .cz ,o zo -= F ). O e iS 6 8 3 .E_ r g / 9 o o o S S ? R R

3. g11-J4/49 '4 t

1 I 9 s l b 9 M I

d 8 w e. e.s. e. a e ./ m o e / e ,r ea we / S e a. e / f-EE E / w' / a >

== e- = w o a = w w a. m .f ze g w / e-e I / w 1 I / ea / a f - e R

o. '

= w ae w i a / o e- /

a. e.e a

/ 3 s g oa a e I e i i.* .e

  • S *.
  • 1 I

?J i a! 4 a +9 \\. t. s a \\ N %, ' a ~. I. .i 2. (s_ o 8 8 e s -E g 8 8 7 E g. a J.'eJngeJoemf Sulppe13 I 1 k 9 I e l '^

J l l o 3w A N l m o =r i = l a = j r x e a u. o u l M 3= m I m o m I e a. e. o. x ae a 1 o a. I w= g H i < w I' g ac a. 1 a s. = I ES S o a = o l a o w a I o w u e neo x o - x 9 4 1

  • o

[ a I e I lI ue la e 8 % f = I I 9 1 1 u g i i. ~ 8 R Io I E I I g iS .__.____.J o t \\ o N o c e _O N cas/u! *agey Suipoogj l

N f o =a edJ o N \\ w a a

= o = a 1 - a w.- W M o 6 = = N 4 .- - = o W uM A.a w - o N .D o j o= x = 3 = o xm o >= o.- < o.

o w w s. o >= W M LaJ o o o w o a S f O T O E o 7 O = C W 6. eo.< R E R / _o o S S 9 R R 2 do gu -2 4 / nis

  • 4 l

6 ) l s t -e

9 3500 3000 u.

  • . 2500 8-2186'?

3 1 / -- we g N - 2000 1 ./ I. M. ~ n t 1500y[ t f 1000 l 4 500 O 10 2D - 30 40 50 50 70 } Time, s i b 2 MOT SPOT CL ADDI MG TEMPER ATURE FOR. 8,55 FT SPLIT IN COLD LEG PIPE AT PUMP DI SCH ARGE Fi gu r e 14.2-9 / r- --n, p

s p o a e a W N v> c me er - N r z o u. u o b M b g es - a l o a u in a. g E oc o n. 6 H w4 g l i o < w 4D as a o n. x o -a w o s o .J o 6 J o w u S ac 1 o z Q I I l 9 f I e o am N l to. i o u e E I s a O R Y I t e,n O E 2 i -o a 6" i R I / I I e~~~-----I I _L o o N o e e sr N o sasful 'agey Bu!poogd e 9 p. +

o _a w a u o m F e so _=

<

b. _J D >= h p a m w - w o m o

=

N >= 4 a .- - = o o s E9 M .a - _. o >= en o A

= x o :

o = m = xo >= >= c = 4 x w o _ w .J o A_ m A >= m [ a w e g o a w o a E O T O S E \\ ~ O di r i o - M te-R. o o g 9 9 R R 9 2...,. i e t 4

f 5 8 + m u j m w e w e. .s 7 e .u

o E

/., ea a = m n. w a -m a m 9 h d ta= . o. .. = j

e. w za w

a 4 ee a ll a w -.a .I ooe + -e a ae uo

  • =

y-e- A e- ,3' .g .- a e a. 4 sa 1 e t - 8 ;: ? l S t N~ 's ,R 's i .\\ r V R / ./ N w i, / N-7 ~ -. - _ _ _ - 4. - -e-g i ,s -g 7 3 -I s I 3,.aangeJosini Sulppe13 'i i, a 4 ~ O g 4 9 ps

l 1 1 o N w n e .a a. N = I e. = N o e n - o u. a e u u @ D D w m ss e n. u. x ac p o a. b l .M W C l S < w I oc a. o a. E-o a w o e I o.a o b J o f a w u i. m I J o x u - z N h o o I n f O O I e V g z 5 2 I u. 1 = d s 1 a I I e -.- - - - l l .o 4Y o N o e e e u o Desfu! *atey Eu tpooy 9 e e t W G e = W

... - ~ ~....... --==m---- I 1 i 1 = o. w m I M E N = - 4 = - =o. a - 6 4 E/3 >= 3 o w a e r-x u.- o = m t, .- m o in x M iD 3 >= W o 9- = - 4 o o = = m w 3 A o e-O E A = w o o - w a u a - a S .- m o M W J o o o L U U CE 4 i 9 5 ) es= 0 .5 R u. ee 4 3 >= R o t F o 8 8 9 R R 9 3. g ;-24/nts 'u t i l e. b G t e

    • =e.e e - -

g s,

i 2 / _8 s!s EE J / 4 s. / I =g 4. 2 E wI C =m E' IE w o 6 w l / EE = x a. t IE 3 -' / g =a oa / 33 / g5 e+ > / -3 s

== 1 1 8.- 8

i..

l s i-1 l a 4a i l j 1 2 1 'nA o .H i h _k _h h*eJa}eJed.41 Sulppeg3 t' e. 9 y

I l w _w i o aw e l a. o a e as I = cc a z w u m v3 .w _o = o. cm i n a. i l x w as D I o o n. ) e w H l w < d >= 4 w l ac a. o n. _x o o w l o a a o w, 1 a o w a o l' w o CC x o e u 1 5

  • O 9 i l

l e a 1 o n Y ll S 5o y R 2 1 l = .a g ~ -o r 1 = 0 i I R I 7_ _ _ _ - - J I l I ^ o o n -e, e e =r N o cas/u! *agry Su!pootj S e / g e* s e

r o af .J g w o a w u m e o e a _m = l as e H H h. = s-a en

a. w _

w n a w z ac N 4 o >- >- = e-o w u n o. n _o >= F3 o a. X er Z 0 a a E w h f o a-e o o a = z w w o .o a. o \\- m h b-w m w a o a w g & u a E 8mo 1 F <e.o m b { .G, R 3 .e >= R sO o o 2 S 9 R, R o o Jo g11-J4/ngs 'q I l l s

E ~

  • w

,i m e e m 04 e= I 45 E 4S i s .I i m b f w z I e a m f a a. 8 e > 4? S O* P = w N e. m 6 w -. t e e 1 a gs

S r e a = s .e e e u > a e .e. S ~ we = s.=,. e 1 I 2 SE + t 1 \\. i. f 1 i 1 t 9 N e# T I t i 1T E l i i ,t +2 1 [ i 4 I .k e i f S h h k l J *eangeaessi Su tppe 33 l l S 9 4 e 4 e

k w e w e a. o N m = =r g ~ = + o u. m e3u W "o D cm o o a. e x u. x o o a. A w w < o w b < W = a. o n. = g o o w o a E o J o w J xo o 8 w a -m = o z U ~ o V 9 ue M = W 4 8 e m .e_ l si f a o u xo m o l 0 1 ^ 8 =- o m, c. o a e e. o o _e, oas/u! *apy Su!poold ,e 9

o o DC .J N g w o i 6 O N N w = x =e \\ g i. H J 3 e. w a w n o m oc u. w < o e w w z L o .o ~ e l w in { o e o o o n. b

= x o :

= 6 A z o > > o =

  • o.

x w o - w s o a. m a m 6 u. m w o S E o o w N g a. u .a ~ 2o E

  • g

-o v i5-t R m ). e ne = ~< e R .Er _o _8 ] E L.. o- = o o o c> c o D_ R _o w w u u

3. g 1-J 4/ngs
  • y 1

l e / e 9 it. A .e

M. De a 3 =, = s a s E = - 2 l. t i = ..e-F_ a t - R . = 1 l l o l O i s a g a y a ....,.... 1..,,,,,, e, I e n

100 90 - 80 70 - 60 rA I I 40 30 20 o End of Blowdown = 16.O s. c .e M o. C ~6 10 o .2 3 m 8 7 6 5 (( g 3 i IL 2 3 1 0 10 20 2 M Time Af ter End of Slowdown, s CORE FLOODING RATE F3R 14.I FT NOT LEG BREAK Fi gu re 14.2-22

w m M N = w i W W N u. m m a z e < w E J e o e u H p r o tn 4 x w u. xN + H u. o n. I, m S A ox = o x u.

  • o w o z x w

\\ 8 o a o m u. I g H M. 8 m w x o o o a. u -m R %o m di uo es= R e .e ~ H o 1 o o E 8 9 R 8 8 8 9 R do 741-J4/ngg 'u p e p.

i 4 e

ggg i

1800 f 1670*F 1600 g'\\ .m i 5,E 1%0 l i i a 5 4 F 1200 i E G 1000 43 I 800 s 600 0 10 20 30 W 50 60 70 Time, s 1 _ e Nf,T SPOT CL AODING TEMP ER ATURE FOR d4.I FT2 HOT LEG BREAK ~~~ Figure 14.2-24 ) 1 ) er s I f i 4*- . ~,, .-,,.4,o..<. ,,n mn.

t u. e. w e ow e E. A 4 R .e. u :c e e . - m o e i e M.= 4 o 6 e -e

  • x e

e O w u a. A e i .a e. w e g a w eC I - s u_ e I

  • 'E

.2 >eH ew w s .aeE 4 .a e-e g aw E .o a q. E e. Z H e .,o - e a6ee3 e_e I e ;: 1 e i e r 1 ee ~ f o C R R R t 9 5 g11 lu/eng snu essu CI E g k F

(_. ..= _--.. ! _,.._&.. m-io* .g .t......_;......-, ......a

p. 3. - I w

l._ . i i l I i 1 i .i a g so ....f...._ k..f..' _ =.= :Q :=_:- 7. g, -.:. - --- -...

m. -

-~.. q 1 . = =. =. -. - - q -- -p e i-

p...g

.9... y. _4 F -... -,p _...i, l l l l I I i. I e. r I, l i. ~~ ~- ~ ---.-~*-~J - ~ - - - ~ '. - -s ,_.L**"'-,_ s.

e. _.

l { j l j t . _........j .l j .. l l i t i I i l l i I i i 5, , so h - i. - - ~ ~-r. * - l. '. i L. .j_~_ [ I i ~ 3 i [ i /\\ l l l i i I i l i l i~! I i i 1 -f,,, Q... =y-\\. s,.'. ) _ -[. - -

_m -

... _y... _ J_ ._.r._..

7.... _. 7_.--

__ 7 3 3 I I I = 3 I % iol -R. =-fbi==,.=. :-.? i.==;- - - -.=..._.. _ ~..- -i H !. -- L - Q .. =.. t. l - _. i,._ __. __ _. 4 _...;_ 6 i - y... _._,__.. ;. p .t ,1 ~~ F ~f i I j i i i i ,j e-.. l _._ l

t... p _;

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,e3 ~ 0 to 2 3 40 to 40 70 40 90 10 0 Tlee, s t,'. NOT SPOT utAT TaasSFER COEFFICIENT FOR I SPLif II COLD LES PIPE AT PuisP 0.55 FT DISCHARGE WITH A SYMMETRICAL. POWER SHAPE Figure 14.2 26 e. /

e 1800 1600 18I0 0 .\\ \\ 't t 1200 j I b 2 i {1000 } j 5 D C 800 7 600 -s j l y 400 20 --- 0 10 3 30 40 50 60 70 Time, s 2 50T SPOT FLU 10 TEMPER ATURE FOR 8.55 FT SPLIT 15 COLD LEG PIPE AT PUMP Ol3CH ARGE WITH A SYMMETRICAL POWER SHAPE Fi gu re 14. 2-27 h

J i

1 s H 8 T 2 T I 2 W I 0 L 0 P E 4 p 1 S G 1 R 2 A er T H F C u S g 55 D E i I F 0 P 9 8 PA M H R U S O P F R TE E AW T O A EP 0 R P 8 L I G PA N C I GI D ER O LT O E L D M F L M O 0 Y E C 7 S R O N A C I 0 s 6 nw o dw lo B f 0 o 5 dn E re t f A 0 1 s 4 e m 6 i 19 T = n w o 4 d w 0 o 3 l B fo dn E 02 i I l I F I 10 1 c1

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o >= et W gg N W 4

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Attachment to A. C. Thics' Letter Dated December 19, 1972 C C:.JC UUCLEAR STATION L':ITS 2 & 3 AEC REQ" ST FC.~, C ITIONAL INTC""ATION n For s=all break analysis calculate the case for a 0.5 ft" break using 14.3 2 the sa=c method as used for the 0.3 ft break. BAW-10052 presents the results of an analysis of loss-of-coolant accidents 1 resulting from small breaks in the reactor coolant system. The validitv, of the small leak evaluation codel was established by analysing the 0.5 ft-break during the blowdown phase of the transient and co= paring the results to those To facilitate this co=parison, assumptions predicted by the large model. pertaining to the bubble rise model and pu=p perfor=ance were made such that consistency with the large model was maintained. In brief, both evaluation models predicted similar results with only slight disagreements occurring in terms of the timing of events. 2 cold To implement the comparison of the two evaluation =odels, the 0.5 ft leg break has now been evaluated using the analytical methods and assu=ptions Section which are strictly applicable to the small leak evaluation model. 3 of BAW-10052 presents the method of analysis used and justification thereof. For the 0.5 f t2 break, the reactor trips in less than 0.1 second at which ti=e pump coastdown is initiated. The core flow, Figure 14.3-1, exhibits a Flow gradual decline in flow rate until the pu=p cavitates at 55 seconds. is then nearly stagnate because of the formation of a steam. bubble in the hot leg. However, at this time a two phase mixture is maintained in the core by flow from the loops and from the high pressure injection pu=p. Adequate cooling is de=onstrated to exist by using pool boiling heat transfer. The power transient, pressure history, inner vessel mixture volume, vessel liquid volume, hot spot heat transfer coefficient, and hot spot cladding temperature responses are shown in Figures 14.3-2 through 14.3-7. The cladding temperature decreases initially due to the loss of power after trip without a substantial loss of flow. Then at 55 seconds the pumps cavitate and the core flow falls to 1% of its initial value. The heat transfer mode is then assumed to be pool film boiling and the heat transfer coefficients are based on Morgan's correlation. As a result, the cladding tempdrature increases to a new equilibrium value of approximately 700 F. The de=perature falls slightly over the next 100 seconds, but then increases again as the effect of pressure on the heat transfer coefficient becomes evident. Since the Morgan heat transfer coefficient decreases with decreasing pressure, loss of pressure causes a rise in temperature to a maximum value of 710 F. The temperatures then decrease as further reductions in the heat transfer jeoefficient are matched by reductions in the decay heat rate. At 400 seconds, the system pressure has decayed to a steady value, the core is covered with mixture, and the engineered safeguard systems are providing more makeup than is being leaked. Therefore, the transient is terminated. I. E. Parks, et al., Multinode Analysis of Gmall Breaks for B&W 2568-MWt CNuclear Plants, EAW-10052, Sabcock & Wilcox, Lynchburg, Virginia, Sept., 1972. 14.3-1

? LIST OF FIGURES Figure Descriotion 2 14.3-1 Core Flow for 0.5 ft Split in Cold Leg Pipe at Pump Discharge 2 14.3-2 , core Ther=al Pcwer for 0.5 ft Split in Cold Leg Pipe i at Pump Discharge 2 14.3-3 Pressure Transient for 0.5 ft Split in Cold Leg Pipe at Pump Discharge 2 14.3-4 Inner Vessel Mixture Volu=e for 0.5 ft Split in Cold Leg Pipe at Pump Discharge 2 14.3-5 Vessel Liquid Volume for 0.5 ft Split in Cold Leg Pipe at Pu=p Discharge 2 14.3-6 Hot Spot Heat Transfer Coefficient for 0.5 ft Split in Cold Leg Pipe at Pump Discharge 14.3-7 Hot Spot Cladding Temperature for 0.5 ft Split in Cold Leg Pipe at Pu=p Discharge h e 14.3-2

O O N = O J t O C9 U e llr E .= 0 O H e= W llp 6 O .J O D g g oc to 4 6 E N O H to 6.= O to . A O K g 3 4 l W b g I Ow H aut %O W J A w== A W DC C O W O M O e E R ? R f 4 e. O I I l O e o C D. O. O. O o w o o F R R s/qt'dotj J e 9 e - ~

a. r m o .a w m a. o <n a se m z n u o 6 <n 6. = t in o cn .o a. w z i M D j o n. 6 u < wN UJ n o 6 o n. J< o x w w > w= o >= 8 o w o uo z o - e J O G. r P oo o o. m =r m n o. s. e. o cn m o o o o o o o o o o Jamed PaZ !puuoN 4 9 0 4 0

6 2400 2000 P = 2200 p si a o , 1600 ~ a. E 1200 3 h

2 k

800 400 A l I 0 0 40 80 120 I60 200 240 28 0 320 360 400 t Time, s 2 PRESSURE TR ANSI ENT FOR 0.5 FT SPLIT IN COLD LEG PIPE AT PUNP DISCHARGE ' Fi gu re 14.3-3 db e e

o 3500 3000 l 2500 e. e ' 2000 ~_ ig i __ _1

~.

_. t_ _. _;. _ _ _ Top of Active E Region 1000 L _.. 500 Bo ttom of ActivejRegion 0 0 40 80 120 160 200 240 28 0 320 360 400 Time, s INNER VESSEL Hi XTURE VOLUME FOR 2 0.5 FT SPLIT IN COLD LEG PIPE AT PUMP DISCHARG[ l Figure 14.3-4 / l 1

O 0 \\ 4500 4000 % 3500 1 200 E k f 2500 Top of Active Region O & 2000 a - __ _ _ _ _ f l 1500 y 1000 Bottom of Active Region 500 0 J 0 40 80 120 160 200 240 280 320 (360 400 Time, s 2 VESSEL LIQUID VOLUME FOR 0.5 FT SPLIT IN COLD LEG PIPE AT PUMP DISCHARGE Figure 14.3-5 9

e 0 e 106 ~ 5 10 .c/ 10' O T t N

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~u 3 E 10 o i3 Y N

E 2

10 ~ N N i / i 10I 0 40 80 120 160 200 2% 280 320 360 W Tlee, s NOT SPOT HEAT TR ANSFER COEFFICIENT FOR 2 0.5 FT SPLIT IN COLD L'.G PIP E AT PUMP 013 CHARGE Fi gu re 14.3-6 /

e O i' 8 50 800 7 50 o'

  • 700

^ g \\ \\

6%

7 \\ = 600 i 550 0 40 80 120 160 20 0 240 280 3 20 360 400 Time, s H0T SPOT CL A0 DING TEMP ER ATURE FO R 2 O. 5 FT SPLIT IM COLO LEG PIP E AT PUMP 01 SCH ARGE Fi gu re 14,3-7 / J}}

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