ML20059B585
| ML20059B585 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 08/24/1990 |
| From: | Ellison R BABCOCK & WILCOX CO. |
| To: | |
| Shared Package | |
| ML20059B582 | List: |
| References | |
| 86-1179795-02, 86-1179795-2, NUDOCS 9008290176 | |
| Download: ML20059B585 (17) | |
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SWNS 20697 2 (11/89)
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f* l', ' ' N . y CALCULATIONAL
SUMMARY
SHEET (CSS) l DOCUMENT IDENTIFIER 86-1179795-02 TITLE ANO-1 HPI FLOW RATE REQUIREMENTS l PREPARED BY: REVIEWED BY:
NAME OM / - b I Sf M NAME I M D N 8 IMf _
SIGNATURE SIGNATUI E b/ W TITLE
!*k DATE N 2V /0 ! TITLE bd DATE IO I of COST CENTER 390 REF. PAGE(S) 17 TM STATEMENT: REVIEWER INDEPENDENCE PURPOSE AND
SUMMARY
OF RESULTS:
This document is a NON-PROPRIETARY release of Revision 01 of this file.
Information has been blanked-out on pages 4, 5. and 15. No new information has been added. This file should not be used for additional Calculations as information important to the subject has been purposely removed.
This file allows the issuance of a NON-PROPRIETARY version of Revision 01 to be released to the NRC.
l-THE FoLLoWING COMPUTER CODES hah. BEEN USED IN THIS DOCUMENT:
CODE / VERSION / REV CODE / VERSION / REV THIS DOCUMENT CONTAINS L AsSUMPTloNS THAT MUST BE VERIFIED prior To USE MONf oN SAFETY.RELATED WORK YES( X) No( )
9008290176 900823 >
PDR ADOCK 05000313 P PDC PAGE I of l7
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l NON PROPRIETARY- 86 1179795-02 l
j TABLE OF CONTENTS EAEE i Purpose 3 !
1 HPI Flow Rate Requirements 3 l Small Break LOCA HPI Requirements 3 ;
Other Transient Requirements on HPI Flow 7 l
Steam Line Break' 7 Steam Generator Tube Rupture 7 Feed and Bleed Cooling 7 Flow Rate Evaluation 8 Margin Assessment 11 Assumptions Used in the Evaluation 11 Discussion of Results 12 HPI Flow Integration 12 Conclusion ,
16 References 17 i
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NON PROPRIETARY 86-1179795 02 l l
Purnose The purpose of this report is to sumarize an evaluation performed to support full power operation at ANO-1. The evaluation is for the High Pressure '
Injection (HPI) system, specifically its performance during small break LOCA
.(SBLOCA) and HPI line break scenarios. i The HPI configuration being evaluated is based on a new configuration of the system using manual valves to provide increased resistance in the four HPI lines to enhance the system performance under conditions where the four HPI ,
lines experience different back pressure conditions. ,
t' The proposed HPI system configuration will be compared to analysis requirements which exist for both the SBLOCA and HPI line break scenarios. ;
The comparison will assume operator action for throttling of a high flow HPI line during HPI line break events. To assess the margins, the configuration will also be evaluated based on no operator action to throttle a high flow ;
line.
HPI Flow Rate Reauirements l The HPI sysi, provides borated cooling water to the reactor coolant system during accicents which produce a primary system depressurization. The -
injection flow provides additional inventory for core cooling and soluble boron for core reactivity control.. The events which require HPI flow, based on FSAR and licensing calculations, are small break loss of coolant accidents
- l. (SBLOCA), steam line break accidents, and steam generator tube rupture (SGTR) l accident. The large break LOCA analyses do not take credit for the HPI flow since the primary system depressurization immediately initiates and allows LPI flow to provide the core cooling. All of the other FSAR events do not place requirements on the HPI system since they lead to insignificant primary system depressurizations, or lead to primary systems pressurizations.
Small Break LOCA HPI Reauirements .
The most stringent requirements are placed on the HPI system by the small break LOCA since the RCS may remain pressurized above the injection pressure of the core flood tanks and the LPI system. As analyzed with the BW ECCS Evaluation Model, the HPI system is assumed to provide flow based on a flow versus pressure table. This table contains the licensed flow rates which have been demonstrated to provide acceptable results for SBLOCA calculations.
The classic small break LOCA is a break in the bottom of the cold leg pump discharge piping downstream of the HPI line connection. The generic HPI flow rates for this event are provided in Table 1 and taken from Reference 1.
A special type of snall break LOCA is a break in the HPI line. The flow rate assumptions are different for this case as compared to the SBLOCA case, in 3
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l NON PROPRIETARY 86-1179795-02 l
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that the back pressures for the broken and intact lines vary greatly. The i generic HPI flow rates required for the HPI line break analysis are given in .
Table 2 and taken from Reference 1. The flow rates given in the tables are l the actual flow rates into the RCS and are not the total pump flow, which l ,
could include a recirculation flow. The flow rates do not account for instrumentation errors. ;
As noted in Tables 1 and 2, the requirements for the HPI flow vary due to flow i balancing by the operator. The analysis for the typical small break LOCA in the pump discharge piping assumes flow balancing 10 minutes following ESAS.
The balancing is assumed to be to such an extent that 70 percent of the flow ;
reaches the RCS for core cooling, while the remaining 30 percent exits the break without reaching the core. The HPI line break, though, assumes isolation of the broken HPI line 20 minutes following ESAS. ; n order to easily demonstrate compliance with the current LOCA analysis, the flow rates listed in these tables must be met. 4 It can also be seen from Table 2 that the requirements for HPI flow at high pressures during an HPI line break event are not defined. This is due to decreasing RCS pressures following the break that result in lower RCS .
pressures as compared to the pressure at which the HPI flow is initiated.
Since the licensing evaluation of the HPI line break quickly results in RCS pressures below 1200 psia, the requirements for the flow at higher pressures are not applicable.
The flow rates in Tables 1 and 2 were used in the generic LOCA analysis with an initial reactor power level of 102% of 2772 MWt. Since main feedwater equivalent to the initial conditions is maintained up to the point of reactor trip, the average primary system energy level is also maintained up to reactor trip. A cnange in the transient due to the power level is seen after reactor trip. At this time, the heat addition to the RCS is driven by the decay heat, which is directly related to the initial powa level; the higher the initial power level, the higher the decay heat. ,
After reactor trip, the rate of reactor coolant system boil-off is due to the ,
mismatch between the heat production in the core and the ability of the HPI system and the break to remove heat from the core and reactor coolant system.
Therefo-e, it follows that a lower power level will result in less heat ,
production in the core after trip which will require less HPI flow to remove ,
the heat. The flow rates in Tables 1 and 2 can be reduced for a lower power level. [
] This method is consistent with Reference 1. These flow reductions are shown in Tables 3 and 4.
The flow rates provided in Tables 3 and 4 are the total flow rates delivered to the core. To meet the analysis assumptions, the ANO-1 HPI flow into the RCS, available for core cooling must meet or exceed these values.
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. - i NON PROPRIETARY 86-1179795-02 i Table 1 I SBLOCA HPI Flow Requirements for flow into the RCS :
Assumed HPI Flows Assumed HPI Flows l First 10 Minutes After 10 Minutes >
(Pre operator (Post-operator l RCS Pressure Action) Action) ;
psig gpa gpm 200 [
6f ': 1 <
1200 '
' l1l 1500 ,
1600 ! .
1800 l ;
2400 l: !
for flow into the RCS Assumed HPI Flows Assumed HPI Flows ,
First 20 Minutes After 20 Minutes-(Pre-operator (Post-operator RCS Pressure Action) Action) :
psig gpm gpm 200 [ ] [ ]
600 [ ] [ ]
1200 ( ) ( )
1500 [ ] [ ]
1600 [ ] [ ]
1800 () ( )
The analysis demonstrates that pressures do not reach these magnitudes l during an HPI line break. Therefore, HPI flow requirements at these -
pressures are undefined for this point in the transient. -t 5
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NON PROPRIETARY 86-1179795 02 Table 3 i SBLOCA HPI Flow Requirements for flow into the RCS for ANO-1 Power level of 2568 MWt :
Assumed HPI Flows Assumed HPI Flows !
First 10 Minutes After 10 Minutes (Pre-operator (Post-operator l RCS Pressure Action) Action) psig gpm gpm 200 208.44 324.24 600 208.44 324.24 1200 176.02 283.48 1 1500 158.42 262.17 1600 151.93 253.84 1800 13f 16 236.23 2400 120.43 168.61 Table 4 HPI Line Break HPI Flow Requirements for flow into the RCS ,
for ANO 1 Power Level of 2568 MWt Assumed HPI Flows Assumed HPI Flows 4 First 20 Minutes After 20 Minutes (Preoperator (Post-operator RCS Pressure Action) Action) .i psig gpm gpm 200 272.09 308.96 600 272.09 308.96 l 1200 197.97 268.19 1500 156.56 Not Applicable
- 1600 138.96 Not Applicable *
- j. 1800 104.22 Not Applicable
- l l The analysis demonstrates that pressures do not reach these magnitudes during an HPI line break. Therefore, HPI flow requirements at these pressures are undefined for this point in the transient.
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l NON PROPRIETARY 86-1179795-02 Other Transient Renuirements on HPI Flow 1
l Steam Line Break j The steam line break event is a secondary overcooling event, which leads to a primary system temperature and pressure decrease. The decrease is sufficient to activate the HP1 system during the event. The HPI flow provides additional cooling to the primary system as well as soluble boron for reactivity control. !
The FSAR analysis credits HPI flow during the event. However, the severity of !
the cooldown also leads to core flood tank injection which provides the large i quantity of soluble boron to assure the reactor remains suberitical.
Since the core flood tanks provide the boron injection necessary to prevent l the core from returning critical following the reactor trip, the HPI system is 1 not constrained by the steam line failure analysis. Therefore, the steam line break accident does not provide any further restrictiotis on HPI flow rates beyond those of the SBLOCA event.
Steam Generator Tube Ruoture I accident does not explicitly state a The flow rate steam for generator tubethe HPI However, rupture FSAR (SGTR) ana lysis states that after actuation, the HPI-flow is sufficient to offset the break flow through the broken tube. The analysis assumed a constant break flow of 432 gpm. Thus the HPI flow, including density changes, must provide this volume at pressures below the 1500 psig aptuation pressure. Assuming the density of the incoming flgid is 62.4 lb/ft and the density of the fluid leaving the break is 45 lb/ft , the required HPI flow is approximately 312 gpm. Since no fluid is directly being lost at the point of injection, the 312 gpm flow rate is the total from all four HPI flow lines.
Since at least one steam generator is available, the majority of the core cooling is provided by the secondary system. Thus, core cooling does not place requirements on the HPI system for this accident. However, an HPI flow rate of 312 gpm must be maintained to meet the FSAR SGTR accident analysis.
Feed and Bleed Coolino Through the years, the derivation of plant emergency procedures and the introduction of new topics into the licensing arena has led to additional conditions being considered which were not part of the original plant design basis. One of these is the total loss of feedwater event which requires the operators to initiate feed and bleed cooling through injection of HPI and t elief through the pressurizer relief valve and pressurizer code safety valves.
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NON PROPRIETARY 86-1179795 02 j HPI cooling through feed and bleed was evaluated by the B&WOG under the AS-5 analytic task. The analysis is summarized in Reference 4. The analysis has shown that for the B&W 177FA lowered loop plant design, core cooling can be ;
maintained through the timely actuation of one HPI pump. The flow rates used !
were based on the current HPI configuration with prethrottled valves in the )
HPI lines, providing approximately 500 gpm into the RCS at 600 psig, l The analysis considered variations in the HPI flow rate (1 and 2 pump cases .
were run) and decay heat level to arrive at a representative system response for the scenario. The conclusions from the analysis are that HPI cooling is an effective means of core cooling. Variations in the HPI flow around the ,
assumed values would lead to slight variations in timing, but would eventually result in a match of core heat removal by the HPI flow. Thus, the feed and bleed cooling analysis does not provide specific flow requirements for the HPI system beyond that for the SBLOCA.
Flow Rate Evaluation The proposed HPI system configuration has been analyzed to determine the flow s)1its between the four HPI .line during SBLOCA and HPI line break scenarios. !
T1e flow splits reflect the potential for the HPI line which is broken to pinch, creating a resistance which may make identification of the broken line
- difficult.
Four HPI line pinch conditions for the line break were evaluated to bound all of the potential pinch conditions. These pinch conditions range from a l
complete pinch, no flow out the broken line, to a full break, maximum flow out the broken line. These cases are identified by the following nomenclature:
I Severe Pinch Complete pinch of the broken line, with no HPI flow exiting the line.
SBLOCA Equivalent Resistance in the pinched line to result in equivalent back pressures across all lines. .
This is the manner in which the HPI flow split will occur for a SBLOCA when all four lines "see" the same RCS pressure.
Limiting Pinch This pinch condition is such that the flow into the RCS matches the post operator action flow I rates of the generic analysis at least one of the pressure conditions.
Full Break This is a full area break of the line, with no pinch restrictions. This case provides maximum HPI flow out of the break.
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i NON PROPRIETARY 86-1179795-02 Table 5 summarizes the expected HPI flow into the RCS at various RCS pressures i for cases which lie between the severe sinch and the limiting pinch. For the cases which lie between the severe pinci and the limiting pinch, the HPI flow ,
i rates without operator action, only valve prethrottle, are sufficient to meet !
or exceed the bounding requirements from the analysis with operator action l (Tables 3 and 4) except at 2400 psig. The 2400 psig condition is not 2 achievable based on existing licensing analysis for the important range of break sizes, which has shown the maximum primary system repressurization for SBLOCAs to reach pnly 1600 1800 psig. Certain very small break sizes, areas less than 0.01 ft can repressurize to this pressure. However, the event is driven by steam generator heat transfer and does not provide restrictions og the HPI flow rate beyond those defined by the SBLOCAs of the 0.02 to 0.1 ft '
range. Therefore, although the 2400 psig flow rate was entered in the flow !
tables in the analysis, the condition cannot be reached during the limiting :
small break LOCA events. As previously discussed, the pressures above 1200 ,
psig for the HPI line break cases are undefined in thJ the pressure will continue to drop and the HPI system will not be required to pump against the :
higher RCS pressure. A quick comparison to the Table 3 and 4 pre-operator action flow requirements verifies that these three cases exceed these requirements also. ;
p Table 5 Comparison of HPI Flow Rates to the Requirements HPI Line Case 14A Case 4 Case 13 SBLOCA Break SBLOCA HPI Flow HPI Flow Severe Equivalent Limiiing Requirements Requirements Pinch Pinch Pinch After After- HPI Flow HPI Flow HPI Flow RCS Operator Operator Into the Into the Into the -
Pressure Action Action RCS RCS RCS nsig (gpm) (gpm) (gpm) (gpm) (gpm) 200 324.24 308.96 453.57 369.73 376.97 600 324.24 308.96 422.11 344.71 335.52 1200 283.48 268.19 368.56 301.69 268.08 1500 262.17 Undefined 338.84 277.21 231.10 1600 253.84 Undefined 325.68 268.45 217.75 1800 236.23 Undefined 295.87 249.59 189.83 2400 168.61 Undefined 181.27 150.73 55.00 If operator action to throttle the high flow line were to be taken for these cases, the flow splits would improve at the pressure at which the action is 9
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NON PROPRIETARY 86-1179795 02 taken and for all lower pressures. This has been demonstrated in Reference 1.
The results are to be expected since throttling the high line increases the ;
resistance in the line, forcing the remaining HPI flow through the good lines.
As the RCS pressure drops, the increased resistance is even more effective in diverting flow from the broken line and even mere flow is directed to the three intact lines. !
The full break case is presented with the flow requirements for both pre and post- operator action flow requirements in Table 6. Additionally, the flow splits associated with balancing flows at 1200 psig are also given, demonstrating the increased flow into the RCS after operator action. Based on Table 6, its is evident that the full break flow splits meet the requirements ]
prior to operator action, but require throttling of the high line to meet the post- operator action requirements. With throttling, the flow splits improve i immensely, assuring large margins for core cooling.
Table 6 i Comparison of Full Break HPI Flow Splits ]
RCS (Ref.1) (Ref. 1) Case 7 Case SA Pressure (Ref. 1) (Ref. 1)
(psig) ,
500 gpm at ?
600 psig Design Point ,
500 gpm at Operator :
HP! Line HPI Line 600 psig Throttling Break Pre- Break Post- Design Point at 1200 psig Operator Operator Action Flow Action Flow Full Break HPI HPI Flow Requirements Requirements Flow Into RCS Into RCS (gpm) (gpm) (gpm) (gpm) 200 272.09 308.96 367.02 441.79 l 600 272.09 308.96 315.14 398.94 1200 197.97 263.19 230.22 328.64
- 182.84 **
1500 156.56
- 166.59 **
1600 138.96
- 132.27 **
1800___ 104.22
- - Not applicable since the primary pressure will not reach this condition during an HPl line break.
- - Not applicable since flow balancing occurs at 1200 psig with pressure decreasing. These conditions cannot be reached during a HPI line break.
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NON PROPRIETARY 86-1179795 02 ;
Marain Assessment In order to quantify the margins which exist to the real core cooling limits, i two additional evaluations were pursued. The first of these was to assume an ;
initial imbalance in the HPI system line flows of 2.5%. This_means that the !
high flow line following the system setup was assumed to be at 27.5% of the total system flow at the design point of 600 psig. The other three lines were modeled to nearly equally split the remaining 72.5% flow. This flow condition ,
was then examined for three of the four HPI line pinch cases, both before and ,
after operator action.
Assumotions Used in the Evaluation The evaluation made certain assumptions to bound the expected plant and HPI system conditions. These assumptions are listed below for reference. -
- 1. The HPI system configuration, initial flow balancing following the system modification, is assumed to be performed using an HPI pump which is at the manufacturer's original performance curve. This is consistent '
with recent pump - performance evaluations at ANO 1. Subsequent flow splits assume the most limiting of either a 6% head degradation or a 65 flow degradation on the HPI pump performance.
- 2. The operator action to be taken when required is to throttle the highest ,
line down to the next highest. In order to quantify margins, the operator is assumed to perform the throttling to a point where the flow ,
in the two lines are within 20 gpm of each other,
- 3. The total instrumentation uncertainty applicable when the operator ,
! performs the throttling is 15 gpm. This assumption in conjunction with I
the second assumption yields an analytic difference in the highest flow line and the next highest of 35 gpm following operator action. >
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- 4. The flow imbalance assumed to exist during initial system flow balancing is 2.5% of the flow. Thus, at the design point of 600 psig, 27.5% of the flow is associated with the high flow line.
- 5. The HPI system configuration, manual valve prethrottle, is such that the total flow rate through the four lines at 600 psig is between 480 and 500 gps. ,
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NON PROPRIETARY 86 1179795 02 Discussion of Results 1
Using the assumptions listed above and analyzing a variety of cases, the !
limiting flow conditions for assessing the margins were developed. These I cases along with the HPI line break flow requirements are given in Tables 7 and 8. The information presented in the tables is taken from Reference 5. !
As shown in Table 7, the imbalance condition still provides margin to the SBLOCA flow requirements for all pressure ranges. Remember that for pressures above 1800 psig, flow requirements do not exist since the SBLOCA analysis has shown that these pressures cannot be reached in the licensing analysis for the ,
limiting SBLOCAs relative to, HPI flow. The limiting break sizes range from approximately 0.02 to 0.1 ft . For this SBLOCA equivalent case, the operator !
is not required to take action since none of the lines will exhibit excessive l flow relative to the others as each line " sees" the same RCS pressure. 1 l
The predicted flow splits (pre and post-operator action) shown in Table 8 )
meet the flow split requirements for both the pre- and post- operator action ;
requirements, including the 35 gpm allowance for operator throttling and 1 instrumentation uncertainty. Thus, the imbalance conditions still results in sufficient HPI flow to meet the requirements for the HPI line break scenario.
The actual HPI system configuration which results from the flow balancing will be evaluated against these conditions to demonstrate that it is bounded by the i calculations summarized in this document. If the imbalance condition is ,
greater, the conditions must be re evaluated to verify the HPI system continues to meet the applicable criteria. ;
HPI Flow Inteoration An additional quantification of the margin was performed for the nominal cases-to assess the ability of the plant to withstand an HPI line break scenario :
without operator action. This provides an additional manner in which to l review the nominal flow split calculations prior to including instrumentation a uncertainties and operator throttling bands.
A representative RCS pressure profile for an HPI line break scenario was generated based on the generic HPI line break analysis for a nominal core -
power of 2772 MWt and the recently analyzed 80%FP ANO 1 specific HPI line break analysis. The RCS pressure profile was conservatively placed between these curves to account for the power level differences and changes in the Evaluation Model which have occurred between the two analyses. The resulting ,
RCS pressure profile was then used to develop and integrated HPI flow versus time for the worst case nominal condition flow splits associated with a full HPI line break, no pinch. The design point which results in the worst conditions is 500 gpm at 600 psig. This results in the least resistance.in the HPI lines, thereby restricting flow the least in the broken line. Again, the flow splits for this case are assumed to be ideal in that instrumentation uncertainty and operator throttling band are assumed to be zero.
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Table 7 l Comparison of Requirements to HP! Flow $plits RCS Pressure SBLOCA-HPI Flow HP! Flow Into RCS psig Requirements into RCS From Ref. 5 Imbalanced Initial Conditions Pre-Operator Post Operator Based on 480 gpm at 600 Action Action psig ;
.SBLOCA Equivalent gpm -
l t 200 208.44 324.24 356.30 ,
600 208.44 324.24 332.16 1200 176.02 283.48 290.70 1500 158.42 262.17 267.09 ,
1600 151.93 253.84 258.66 <
1800 138.96 236.23 240.37 l
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NON PROPRIETARY 86-1179795-02 -
Table 8 ..
Comparison of Requirements to HPI Flow Splits
, Pressure Flow Requirements into From Ref. 5 From Ref. 5 ,
psig RCS Imbalanced Initial Conditions Operator action to l
- throttle to within 35 9pm j Pre- Post- Based on 480 gpa at 600 Operator Operator psig ;
Action Action
- gpa gpa Based on 500 Post- Post gpa at 600 Operator Operator i psig Action from Action from
- Limiting 480 gym at 500 gym at SBLOCA Pinch Break Full Line 600 psig 600 psig l Equivalent gpa Break Initial Initial gpa Condition Condition gpa j 9pm 9pm 200 272.09 308.% 356.30 373.85 351.81 381.01 402.23 600 272.09 308. % 332.16 333.46 298.66 341.93 359.32 I 1200 197.97 268.19 290.70 268.00 211.57 278.13 288.88 !
1500 156.56 NA 267.09 232.18 162.93 M M -
1600 138. % NA 258.66 219.03 146.08 NA NA 1800 104.22 NA 240.37 192.03 110.64 NA NA 2400 NA NA 145.19 59.99 0.00 NA NA '
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.- l NON PROPRIETARY 86 1179795-02 1 The flow splits associated with full break case in combination with the RCS pressure profile resulted in the data provided in Table 9. This information I is taken from Case 7 of. Reference 4 Only the data late in the event where the system inventories are approaching minimums are presented. As shown in the table, the integrated HPI flow for the worst case conditions and no operator action will still ensure the injection requirements of the 2772 MWt i analysis are met.
Table 9 i Integrated HPI Flow Results Versus ;
HPI Injection Requirements for. ..
a Nominal Plant Power of 2772 MWt (Data taken from Case 7 of Reference 4) ,
(
HPI Line Break RCS HPI Line Break Integrated HPI Transient Pressure Integrated HPI Flow Into the Time Flow Into the RCS RCS for a Full ,
from Generic Break Case ',
(sec) (psig) 2772 MWt Analysis (No Pinch) ,
(lbm) (lbe) l
[ ] [ ] [ ] [ ]
[ ] [ ] [ ] [ 1 ,
[ ] [ ] [ ] [ ]
[ ] [ ] [ ] [ ]
P
[ ] [ ] [ ] [ ]
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NON PROPRIETARY 86-1179795 02
'l Conclusions 1
The limiting HPI flow requirements are based on the small break LCCA and HPI line break LOCA events. The HPI flow rate requirements for a power level of ,
2568 MWt are given in Tables 3 and 4. For an assumed operator action to l throttle the highest HPI line flow down to the next highest line flow, the flow rates for the proposed ANO 1 configuration easily meet the requirements both before and after operator action has been taken. This provides the j greatest margins for core cooling during SBLOCAs and HPI-line break scenarios.
For an initial flow imbalance of 2.5% flow, operator action to bring the high I flow line to within 35 gpm of the next highest line will ensure the flow requirements for both SBLOCA and HPI line break scenarios are still met. 1 Additionally, if no operator action is assumed for the nominal cases (no errors and a zero imbalance configuration initially), it has been shown that sufficient HPI is injected during an HPI line break event to meet the total injection requirements from the generic 2772 MWt analysis. These two approaches demonstrate the large margins which exist for the proposed HPI configuration at ANO 1.
3 Therefore, the performance of the proposed HPI system configuration at ANO-1 has been shown to provide more than sufficient HPI injection flow to meet the licensing requirements at a nominal power level of 2568 MWt.
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1 References j
- 1. Design Memo M.C. Gharakhani to F.J. Levandowski, "HPI Flow Split During a Small Break LOCA" Contract 620-0005, File. Point 20A3.3, December 20, '
1979, Reviewed and approved by R.C. Jones.
- 2. B&W Document Number 86-1173989-01. " Transient Information Document Owner's Group Task AS-5 Evaluation of HPI Cooling", February 1989.
- 3. 32 1179896 00, "ANO-1 HPI System Analysis", Contract 582-7473, Task 463.
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