AEP-NRC-2009-25, Small Break Loss-of-Coolant Accident Evaluation Model Reanalysis
| ML091100153 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 03/30/2009 |
| From: | Hruby R Indiana Michigan Power Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| AEP-NRC-2009-25 | |
| Download: ML091100153 (111) | |
Text
Indiana Michigan Power Company Nuclear Generation Group INDIANA One Cook Place MICHIGAN Bridgman, MI 49106 POWER aep.com March 30, 2009 AEP-NRC-2009-25 10 CFR 50.46 Docket No.: 50-316 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Donald C. Cook Nuclear Plant Unit 2 SMALL BREAK LOSS-OF-COOLANT ACCIDENT EVALUATION MODEL REANALYSIS
References:
- 1. Letter from M. W. Rencheck, Indiana Michigan Power Company (I&M), to Nuclear Regulatory Commission (NRC) Document Control Desk, "Donald C. Cook Nuclear Plant Units 1 and 2, Errors in Loss-of-Coolant Accident Evaluation Models," C1299-04, dated December 9, 1999 (ML993510144).
- 2. Letter from S. A. Greenlee, I&M, to NRC Document Control Desk, "Donald C. Cook Nuclear Plant Units 1 and 2, Annual Report of Loss-of-Coolant Accident Evaluation Model Changes," C0801-19, dated August 31, 2001 (ML012490022).
- 3. Letter from J. N. Jensen, I&M, to NRC Document Control Desk, "Donald C. Cook Nuclear Plant Unit 1, Completion of Commitment Regarding Small Break Loss-of-Coolant Accident Analysis 8.75-inch Case (TAC No.
MD5297)," AEP-NRC-2008-11, dated July 24, 2008 (ML082170376).
By Reference 1, Indiana Michigan Power Company (I&M), the licensee for Donald C. Cook Nuclear Plant (CNP) Unit 2, stated that it would submit a reanalysis of the high head safety injection (HHSI) cross-tie valve closed case for a Unit 2 small break loss-of-coolant accident (SBLOCA) pursuant to 10 CFR 50.46(a)(3)(ii). By Reference 2, I&M stated that it would submit reanalyses of an HHSI cross-tie valve closed case and an HHSI cross-tie valve open case for a Unit 2 SBLOCA pursuant to 10 CFR 50.46(a)(3)(ii).
The enclosure provides a report of the Unit 2 SBLOCA reanalyses of the HHSI cross-tie valve closed case and the HHSI cross-tie valve open case for a Unit 2 SBLOCA performed using the Westinghouse NOTRUMP Small Break LOCA Emergency Core Cooling System Evaluation A,6
U. S. Nuclear Regulatory Commission AEP-NRC-2009-25 Page 2 Model (NOTRUMP-EM), with the COSI steam condensation model. The NOTRUMP-EM model was used for the current Unit 2 analysis of record. The NOTRUMP-EM with the COSI steam condensation model was used for the current Unit 1 SBLOCA analyses of record transmitted by Reference 3. The NOTRUMP-EM and COSI steam condensation models were approved by the Nuclear Regulatory Commission for use by Westinghouse designed plants in May 1985 and August 1996, respectively.
As described in the enclosed report, the results of the revised CNP Unit 2 SBLOCA analyses with HHSI cross-tie valve closed case and HHSI cross-tie valve open case conform to the emergency core cooling system acceptance criteria of 10 CFR 50.46.
There are no new commitments in this submittal. Should you have any questions, please contact Mr. John Zwolinski, Regulatory Affairs Manager, at (269) 466-2478.
Sincerely, Raymond A. Hruby, Jr.
Vice President - Site Support Services JRW/rdw Enclosure c: T. A. Beltz - NRC Washington, DC K. D. Curry - AEP Ft. Wayne J. T. King - MPSC MDEQ - WHMD/RPS NRC Resident Inspector M. A. Satorius, NRC R-1Il
Enclosure to AEP-NRC-2009-25 Donald C. Cook Nuclear Plant Unit 2 Small Break LOCAAnalysis Report
Westinghouse Non-Proprietary Class 3 D. C. COOK UNIT 2 SMALL BREAK LOCA ANALYSIS REPORT 1 INTRODUCTION The purpose of this report is to document the small break loss of coolant accident (SBLOCA) analyses performed for Donald C. Cook Nuclear Plant Unit 2 (D. C. Cook Unit 2) with two different configurations of the emergency core cooling system (ECCS) cross-tie valves during the injection phase of the transient: 1) With the high head safety injection (HHSI) cross-tie isolated and residual heat removal (RHR) cross-tie valve(s) open at a core power level of 3304 MWt (3315 MWt, including 0.34%
uncertainty) and 2) With both HHSI and RHR cross-tie valve(s) open at a core power level of 3600 MWt (3612 MWt, including 0.34% uncertainty). (Note: Hereafter these two cases are referred to by their respective core power levels.) Both analyses were performed with both the HHSI and RHR cross-ties isolated during the recirculation phase of the transient. (It is noteworthy that HHSI refers to the fluid system designated as the Safety Injection (SI) system in the D. C. Cook Unit 2 Technical Specifications and Bases, and in previous model change and error reports submitted pursuant to 10 CFR 50.46.) The purpose of analyzing the SBLOCA is to demonstrate compliance with the 10 CFR 50.46 requirements (Reference 1). Important input assumptions, as well as analytical models and methodology for the SBLOCA analyses are contained in subsequent sections. Results are provided in the form of tables and figures, as well as more detailed descriptions of the limiting transients. The analyses have shown that no design or regulatory limit related to the SBLOCA transient would be exceeded due to plant operation with the ECCS cross-ties configurations, power levels and the associated plant parameters outlined in this report.
2 INPUT PARAMETERS AND ASSUMPTIONS The important plant conditions and features for D. C. Cook Unit 2 that are supported by these analyses are listed in Table 1. Additional considerations for several parameters identified in Table 1 are discussed below.
Figures 1 and 2 depict the hot rod axial power shapes modeled in the SBLOCA analyses for the 3304 MWt and 3600 MWt core power levels, respectively. These shapes were chosen because they represent a distribution with power concentrated in the upper regions of the core (the axial offset is +13%). Such a distribution is limiting for SBLOCA since it minimizes coolant swell while maximizing vapor superheating and fuel rod heat generation at the uncovered elevations. The chosen power shapes have been conservatively scaled to standard 2-line segment K(Z) envelopes based on the peaking factors shown in Table 1 for each power level analyzed.
Figures 3 through 6 and 7 through 10 provide the ECCS flows modeled in the SBLOCA analysis at 3304 MWt core power and 3600 MWt core power, respectively. Figures 3, 4, 7 and 8 show the ECCS pumped injection flow versus pressure curves utilized during the injection phase and Figures 5, 6, 9 and 10 show the ECCS pumped injection flow versus pressure curves utilized during the cold leg recirculation phase (with both HHSI and RHR cross-ties isolated). Figures 3, 5, 7 and 9 show the flows from one charging (CHG) pump, one HHSI pump and one RHR pump, where the broken (or faulted) loop flow spills to reactor coolant system (RCS) pressure. Figures 4, 6, 8 and 10 show flows from one CHG pump, one HHSI pump and one RHR pump, where the faulted loop CHG flow spills-to RCS pressure and the faulted 1
Westinghouse Non-Proprietary Class 3 loop HHSI/RHR flow spills to 0 psig containment pressure, because the break is postulated along the accumulator line. Note that hereafter, pumped injection subsystems of the ECCS (CHG; HHSI and RHR) are referred to collectively as safety injection (SI).
The analyses utilized an adjusted nominal vessel average temperature (Tavg) of 578.2°F (with + 4°F uncertainty specified by NOTRUMP-EM) to support the D. C. Cook Unit 2 specific Tavg value of 578.1°F with +4.1 °F uncertainty. The analysis supports operation for a nominal full-power Tavg range of 547.6°F to 578.1°F with +4.1°F/-5.6°F uncertainty. Additionally, the analysis utilizes a nominal pressurizer pressure of 2250 psia (plus +62.6 psi uncertainty) and supports operation at nominal pressurizer pressures of 2 100 psia and 2250 psia with +/-62.6 psi uncertainty.
3 DESCRIPTION OF ANALYSES AND EVALUATIONS 3.1 ANALYTICAL MODEL The requirements for an acceptable ECCS evaluation model are presented in Appendix K of 10 CFR 50 (Reference 1). For LOCAs due to Small Breaks, less than 1 square foot in area, the Westinghouse NOTRUMP SBLOCA Emergency Core Cooling System (ECCS) Evaluation Model (References 2 and 3) with the improved condensation model (COSI) (Reference 4) is used. The Westinghouse NOTRUMP SBLOCA ECCS Evaluation Model (NOTRUMP-EM) was developed to determine the RCS response to design basis SBLOCAs, and to address NRC concerns expressed in NUREG-0611 (Reference 5).
The NOTRUMP-EM consists of the NOTRUMP and LOCTA-1V computer codes. The NOTRUMP code is employed to calculate the transient depressurization of the RCS, as well as to describe the mass and energy release of the fluid flow through the break. Among the features of the NOTRUMP code are:
calculation of thermal non-equilibrium in all fluid volumes, flow regime-dependent drift flux calculations with counter-current flooding limitations, mixture level tracking logic in multiple-stacked fluid nodes, regime-dependent drift flux calculations in multiple-stacked fluid nodes and regime-dependent heat transfer correlations. These features -provide NOTRUMP with the capability to accurately calculate the mass and energy distribution throughout the RCS during the course of a SBLOCA.
The RCS model is nodalized into volumes interconnected by flow paths. The broken loop and each of the three intact loops are modeled explicitly, primarily to model the asymmetric SI flows that result from closure of one or both valves in the HHSI cross-tie. Transient behavior of the system is determined from the governing conservation equations of mass, energy, and momentum. The multi-node capability of the program enables explicit, detailed spatial representation of various system components which, among other capabilities, enables a calculation of the behavior of the loop seal during a SBLOCA. The reactor core is represented as heated control volumes with associated phase separation models to permit transient mixture height calculations.
Fuel cladding thermal analyses are performed with SBLOCTA, a SBLOCA version of the LOCTA-1V code (Reference 3), using the NOTRUMP calculated core pressure, fuel rod power history, uncovered core steam flow and mixture heights as boundary conditions. The SBLOCTA code models the hot rod and the average hot assembly rod, assuming a conservative power distribution that is skewed to the top of the core. Figure 11 illustrates the code interface for the Small Break Model.
2
Westinghouse Non-Proprietary Class 3 3.2 ANALYSES The SBLOCA analysis for D. C. Cook Unit 2 at 3304 MWt core power, considered a spectrum of eleven different break cases, including 1.5-, 2-, 2.5-, 2.75-, 3-, 3.25-, 3.5-, 3.75-, 4-, 6- and 8.75-inch breaks. The 3.5-inch break was found to be limiting for peak cladding temperature (PCT) and 3.0-inch break was found to be limiting for maximum local transient oxidation. The 1.5-inch case showed no core uncovery and the 6.0-inch case showed minimal core uncovery (as can be seen in Figure 47) and therefore PCT information was not calculated for these cases.
The SBLOCA analysis for D. C. Cook Unit 2 at 3600 MWt core power, considered a spectrum of eight different break cases, including 1.5-, 2-, 3-, 4-, 6-, 8.5-, 8.75- and 9-inch breaks. The 8.75-inch break was found to be limiting for both PCT and maximum local transient oxidation. The 1.5- and 8.5-inch breaks showed no core uncovery and the 6.0-inch case showed minimal core uncovery (as can be seen in Figure
- 74) and therefore PCT information was not calculated for these cases.
The most limiting single active failure used for a SBLOCA is that of an emergency power train failure which results in the loss of one complete train of ECCS components. In addition, a Loss-of-Offsite Power (LOOP) is postulated to occur coincident with reactor trip. This means that with the assumed loss of emergency power there is a loss of one CHG pump, one HHSI pump and one RHR pump. The SBLOCA analyses performed for D. C. Cook Unit 2 model the ECCS injection phase and cold leg recirculation phase flows as being delivered to both the intact and faulted loops at the RCS backpressure for breaks smaller than the accumulator line inner diameter (1.5-inch through 8.5-inch breaks) and at containment pressure for breaks equal to or greater than the accumulator line inner diameter (_ 8.75-inch breaks). Note that for the breaks > 8.75-inch, the CHG flow is assumed to inject into the broken loop cold leg at the RCS backpressure since it is not affected by the accumulator line break (CHG injects via a separate connection to the cold leg). The flows for these scenarios are illustrated in Figures 3 through 10 for the two power levels analyzed. The LOOP and the failure of an emergency diesel generator to start as the limiting single failure for SBLOCA is part of the NRC approved methodology. The single failure assumption is extremely limiting due to the fact that one train of SI, one motor driven auxiliary feedwater (AFW) pump, and power to the reactor coolant pumps (RCPs). are all modeled to be lost. Any other active single failure would not result in a more limiting scenario since increased SI flow would improve the overall transient results.
Prior to break initiation, the plant is modeled to be in a full power (100.34%) equilibrium condition (i.e., the heat generated in the core is being removed via the secondary system) for the nominal power level assumed in each analysis. Other initial plant conditions used in the analysis are given in Table 1.
Subsequent to the break opening, a period of reactor coolant system blowdown ensues in which the heat from fission product decay, the hot reactor internals, and the reactor vessel continues to be transferred to the RCS fluid. The heat transfer between the RCS and the secondary system may be in either direction and is a function of the relative temperatures of the primary and secondary conditions. In the case of continuous heat addition to the secondary side during a period of quasi-equilibrium, an increase in the secondary system pressure (due to the assumed turbine trip following the reactor trip discussed below) results in steam relief via the steam generator safety valves.
When a SBLOCA occurs, depressurization of the RCS causes fluid to flow into the loops from the pressurizer resulting in a pressure and level decrease in the pressurizer. The reactor trip signal 3
Westinghouse Non-Proprietary Class 3 subsequently occurs when the pressurizer low-pressure reactor trip setpoint, conservatively modeled as 1860 psia, is reached. LOOP is postulated to occur coincident with reactor trip. The SI signal is generated when the pressurizer low-pressure SI setpoint, conservatively modeled as 1715 psia, is reached.
SI flow is delayed 54 seconds after the occurrence of the low-pressure condition. This delay conservatively accounts for signal processing, diesel generator start up and emergency power bus loading consistent with the LOOP coincident with reactor trip, as well as the pump acceleration and valve delays.
The following countermeasures limit the consequences of the accident in two ways:
- 1. Reactor trip and borated water injection supplement void formation in causing a rapid reduction of nuclear power to a residual level corresponding to the delayed fission and fission product decay. No credit is taken in the SBLOCA analysis for the boron content of the injection water. In addition, credit is taken in the'SBLOCA analysis for the insertion of Rod Cluster Control Assemblies (RCCAs) subsequent to the reactor trip signal, considering the most reactive RCCA is stuck in the full out position. A rod drop time of 2.7 seconds was used while also considering an additional 2 seconds for the signal processing delay time. Therefore, a total delay time of 4.7 seconds from the time of reactor trip signal to full rod insertion was used in the SBLOCA analysis.
- 2. Injection of borated water provides sufficient flooding of the core to prevent excessive cladding temperatures.
During the earlier part of the Small Break transient (prior to the postulated LOOP coincident with reactor trip), the loss of flow through the break is not sufficient to overcome the positive core flow maintained by the RCPs. During this period, upward flow through the core is maintained. However, following the RCP trip (due to a LOOP) and subsequent pump coastdown, a period of core uncovery occurs. Ultimately, the Small Break transient is terminated when the top of the core is recovered or the core mixing level is increasing, and ECCS flow provided to the RCS exceeds the break flow rate.
The core heat transfer mechanisms associated with the Small Break transient include the break itself, the injected ECCS water, and the heat transferred from the RCS to the steam generator secondary side. Main feedwater (MFW) is conservatively isolated in 8 seconds following the generation of the pressurizer low-pressure SI signal. Additional makeup water is also provided to the secondary using the AFW system.
An AFW actuation signal is derived from the pressurizer low-pressure reactor trip signal and results in the delivery of AFW flow 80 seconds after reactor trip. The heat transferred to the secondary side of the steam generator aids in the reduction of the RCS pressure.
Should the RCS depressurize to approximately 600 psia (accumulator minimum pressure), the cold leg accumulators begin to inject borated water into the reactor coolant loops as reflected in Tables 14 and 15.
4 ACCEPTANCE CRITERIA AND RESULTS The acceptance criteria for the LOCA are described in 10 CFR 50.46 (Reference 1) as follows:
4
Westinghouse Non-Proprietary Class 3
- 1. The calculated maximum fuel element cladding temperature shall not exceed 2200'F.
- 2. The calculated total oxidation of the cladding shall nowhere exceed 0.17 times the total cladding thickness before oxidation.
- 3. The calculated total amount of hydrogen generated from the chemical reaction of the cladding with water or steam shall not exceed 0.01 times the hypothetical amount that would be generated if all of the metal in the cladding cylinders surrounding the fuel, excluding the cladding surrounding the plenum volume, were to react.
- 4. Calculated changes in core geometry shall be such that the core remains amenable to cooling.
- 5. After any calculated successful initial operation of the ECCS, the calculated core temperature shall be maintained at an acceptably low value and decay heat shall be removed for the extended period of time required by the long-lived radioactivity remaining in the core.
Criteria 1 through 3 are explicitly covered by the SBLOCA analyses.
For criterion 4, the appropriate core geometry was modeled in the SBLOCA analyses. The results based on this geometry satisfy the PCT criterion of 10 CFR 50.46 (Reference 1) and consequently, demonstrate that the core remains amenable to cooling.
For criterion 5, Long-Term Core Cooling (LTCC) considerations are not directly applicable to the SBLOCA transient analyses addressed herein, with the exception of predicting switchover from ECCS injection phase to ECCS recirculation phase and ensuring the SBLOCA transient remains terminated.
The acceptance criteria were established to provide a significant margin in ECCS performance following a LOCA.
In order to determine the conditions that produced the most limiting SBLOCA case (as determined by the highest calculated PCT and the maximum local transient oxidation), eleven break cases at the core power of 3304 MWt and eight break cases at the core power of 3600 MWt were examined for D. C. Cook Unit
- 2. These cases were investigated to capture the most severe postulated SBLOCA event. The following discussion provides insight into the analyzed conditions.
The results of the generic study documented in Reference 6 demonstrate that the cold leg break location is limiting with respect to postulated cold leg, hot leg and pump suction leg break locations. The PCT results for D. C. Cook Unit 2 are shown in Tables 10, 11, 12 and 13 and Tables 14 and 15 provide the key transient event times.
4.1 LIMITING BREAK CASES 4.1.1 3304 MWt The SBLOCA analysis for D. C. Cook Unit 2 at 3304 MWt core power showed that the 3.5- and 3.0-inch breaks are the limiting cases (the 3.5-inch break case with the limiting PCT and the 3.0-inch break case 5
Westinghouse Non-Proprietary Class 3 with the maximum local transient oxidation). A time-in-life study considering clad burst was performed for both the 3.5- and 3.0-inch breaks to determine the limiting PCT and the maximum local transient oxidation. The results showed that the limiting PCT occurs at beginning-of-life (BOL) for the 3.5-inch break and the maximum local transient oxidation occurs at 20,000 MWD/MTU for the 3.0-inch break.
Peak Cladding Temperature Based on the time-in-life study, the limiting PCT is 1722°F for the 3.5-inch break at BOL. A summary of the transient response for the limiting PCT case is shown in Figures 12 through 22. These figures present the response of the following parameters:
- RCS Pressure 0 Core Mixture Level
- Core Exit Vapor Temperature
- Broken and Intact Loops Secondary Pressures 0 Break Vapor Flow Rate
- Break Liquid Flow Rate
- Broken and Intact Loops Accumulator Flow Rates
- Broken and Intact Loops Pumped Safety Injection Flow Rates
- Rod Film Heat Transfer Coefficient at PCT Elevation Upon initiation of the 3304 MWt limiting 3.5-inch break, there is an initial rapid depressurization of the RCS followed by a quasi-equilibrium condition at approximately 1150 psia, slightly above the main steam safety valve (MSSV) lift pressure (see Figure 12). A reactor trip signal is generated at 13.9 seconds followed by a SI signal at 20.8 seconds. The quasi-equilibrium is upset when the loop seal clears in the faulted loop at approximately 398 seconds, creating a vapor vent path between the top of the core and the break in the cold leg.. During this initial part of the transient, the break flow is entirely liquid, which along with the low SI flow rates associated with the high system pressure results in a net reduction in the primary system mass. Core uncovery begins at approximately 745 seconds (see Figure 13), leading to the start of cladding heatup (Figure 20). The accumulator injection setpoint is reached at approximately 1104 seconds (see Figure 18). The peak top core vapor temperature (Figure 14) and the corresponding PCT (Figure 20) occur at approximately 1312 seconds. The PCT occurs near the time when the core is most deeply uncovered and the top of the core is being cooled by steam. This time is characterized by the highest vapor superheating above the mixture level (refer to Figure 14). The limiting PCT time-in-life was determined to be BOL.
A comparison of the flow provided by the SI system to each loop is shown in Figure 19. The cold leg break vapor and liquid mass flow rates are provided in Figures 16 and 17, respectively. Figures 21 and 22 provide additional information on the hot spot fluid temperature at the PCT elevation and hot rod surface heat transfer coefficient at the PCT elevation, respectively. Figure 15 depicts the secondary side pressure for both the intact and broken loops for the limiting PCT break case.
6
Westinghouse Non-Proprietary Class 3 Maximum Local Oxidation The maximum local transient oxidation was calculated for the 3.0-inch break. Based on the time-in-life study, the maximum local transient oxidation is 5.24% at 20,000 MWD/MTU. The limiting transient oxidation occurs at the hot rod burst elevation and includes both outside oxidation and post-rupture inside oxidation in the burst region. Pre-existing (pre-transient) oxidation was also considered and the sum of the pre-transient and transient oxidation remains below 17% at all times in life, for all fuel resident in the core.
Core Wide Average Oxidation Tables 10 and 11 indicate that, the core wide average oxidation for all cases is less than 1%. Therefore the calculated total amount of hydrogen generation is less than the 1% limit defined by 10 CFR 50.46 (Reference 1).
Additional Break Cases Generic studies documented in Reference 6 determined that the limiting PCT Small Break transient occurs for breaks of less than 10-inches in diameter in the cold leg. For D. C. Cook Unit 2 at 3304 MWt core power, the limiting PCT is captured by the 1.5-, 2-, 2.5-, 2.75-, 3-, 3.25-, 3.5-, 3.75-, 4-, 6- and 8.75-inch break spectrum. The BOL results for these break cases are shown in Table 10. Figures 23 through 50 address the non-limiting cases (1.5-, 2-, 2.5-, 2.75-, 3-, 3.25-, 3.75-, 4-, 6- and 8.75-inch) analyzed.
The 1.5-inch case showed no core uncovery and the 6.0-inch case showed minimal core uncovery (as can be seen in Figure 47), therefore PCT information was not calculated for these two cases. The plots for each of the additional non-limiting break cases include:
- 1. RCS Pressure
- 2. Core Mixture Level
The PCTs for each of the additional breaks considered are shown in Table 10 and are less than the limiting 3.5-inch break case.
4.1.2 3600 MWt The SBLOCA analysis for D. C. Cook Unit 2 at 3600 MWt core power showed that the 8.75-inch break is the limiting case for PCT and maximum local transient oxidation. A time-in-life study to determine the limiting PCT and maximum local transient oxidation considering clad burst concluded that the limiting PCT and maximum local transient oxidation occur at BOL.
Peak Cladding Temperature Based on the time-in-life study, the limiting PCT is 1691'F for the 8.75-inch break at BOL. A summary of the transient response for the limiting PCT case is shown in Figures 51 through 61. These figures present the response of the following parameters:
7
Westinghouse Non-Proprietary Class 3
- RCS Pressure
- Core Mixture Level
- Core Exit Vapor Temperature
- Broken and Intact Loops Secondary Pressures
- Break Vapor Flow Rate
- Break Liquid Flow Rate
- Broken and Intact Loops Accumulator Flow Rates
- Broken and Intact Loops Pumped Safety Injection Flow Rates 0 Clad Temperature at PCT Elevation 0 Hot Spot Fluid Temperature at PCT Elevation
- Rod Film Heat Transfer Coefficient at PCT Elevation Upon initiation of the 3600 MWt limiting 8.75-inch break, there is an initial rapid depressurization of the RCS followed by a very brief period of slower depressurization at approximately 1150 psia; slightly above the MSSV lift pressure (see Figure 51). A reactor trip signal is generated at 4.8 seconds followed by a SI signal at 7.7 seconds. The rate of depressurization begins to increase once the loop seal clears in the faulted loop at approximately 26 seconds, creating a vapor vent path between the top of the core and the break in the cold leg. During this initial part of the transient, the break flow is entirely liquid, which along with the low SI flow rates associated with the high system pressure results in a net reduction in the primary system mass. The accumulator injection setpoint is reached at approximately 168 seconds (see Figure 57). There is no core uncovery during the injection phase, but core uncovery begins during the recirculation phase at approximately 2339 seconds (see Figure 52), leading to the start of cladding heatup (Figure 59). The peak top core vapor temperature (Figure 53) and the corresponding PCT (Figure 59) occur at approximately 3412 seconds. The PCT occurs near the time when the core is most deeply uncovered and the top of the core is being cooled by steam. This time is characterized by the highest vapor superheating above the mixture level (refer to Figure 53). The limiting PCT time-in-life was determined to be BOL.
A comparison of the flow provided by the SI system to each loop is shown in Figure 58. The cold leg break vapor and liquid mass flow rates are provided in Figures 55 and 56, respectively. Figures 60 and 61 provide additional information on the hot spot fluid temperature at the PCT elevation and hot rod surface heat transfer coefficient at the PCT elevation, respectively. Figure 54 depicts the secondary side pressure for both the intact and broken loops for the limiting PCT break case.
Maximum Local Oxidation The maximum local transient oxidation was calculated for the 8.75-inch break. Based on the time-in-life study, the maximum local transient oxidation is 3.98% at BOL. The limiting transient oxidation occurs at the hot rod burst elevation and includes both outside oxidation and post-rupture inside oxidation in the burst region. Pre-existing (pre-transient) oxidation was also considered and the sum of the pre-transient and transient oxidation remains below 17% at all times in life, for all fuel resident in the core.
Core Wide Average Oxidation Tables 12 and 13 indicate that the core wide average oxidation for all cases is less than 1%. Therefore the calculated total amount of hydrogen generation is less than the 1% limit defined by 10 CFR 50.46 8
Westinghouse Non-Proprietary Class 3 (Reference 1).
Additional Break Cases Generic studies documented in Reference 6 determined that the limiting PCT Small Break transient occurs for breaks of less than 10-inches in diameter in the cold leg. For D. C. Cook Unit 2 at 3600 MWt core power, the limiting PCT is captured by the 1.5-, 2-, 3-, 4-, 6-, 8.5-, 8.75- and 9-inch break spectrum.
The BOL results for these break cases are shown in Table 12. Figures 62 through 79 address the non-limiting cases (1.5-, 2-, 3-, 4-, 6-, 8.5- and 9-inch) analyzed. The 1.5- and 8.5-inch breaks showed no core uncovery and the 6.0-inch case showed minimal core uncovery (as can be seen in Figure 74), therefore PCT information was not calculated for these three cases. The plots for each of the additional non-limiting break cases include:
- 1. RCS Pressure
- 2. Core Mixture Level
The PCTs for each of the additional breaks considered are shown in Table 12 and are less than the limiting 8.75-inch break case.
4.1.3 Switchover from ECCS Injection Phase to ECCS Recirculation Phase When the refueling water storage tank (RWST) volume of 280,000 gallons is delivered via SI and containment spray, NOTRUMP predicts switchover from ECCS injection phase to ECCS recirculation phase. At that time RHR flow is re-aligned to the sump and an interruption in RHR flow for up to 5 minutes may occur. For break cases that have a calculated RCS pressure at or below the RHR cut-in pressure, the 5 minute interruption in RHR flow is considered. The applicable transients were shown to satisfy the analysis termination conditions, as discussed in more detail below.
4.1.4 Transient Termination The 10 CFR 50.46 criteria (Reference 1) continue to be satisfied beyond the end of the calculated transient due to the presence of the following conditions:
- 1. The RCS pressure is gradually decreasing or reached equilibrium.
- 2. The net mass inventory is increasing or reached equilibrium.
- 3. The core mixture level is recovered, or recovering due to increasing mass inventory.
- 4. As the RCS inventory continues to gradually increase, the core mixture level will continue to increase and the fuel cladding temperatures will continue to decline indicating that the temperature excursion is terminated.
5 CONCLUSIONS The SBLOCA analyses for D. C. Cook Unit 2 considered a break spectrum of 1.5-, 2-, 2.5-, 2.75-, 3-,
3.25-, 3.5-, 3.75-, 4-, 6-, and 8.75-inch diameters at a core power of 3304 MWt and a break spectrum of
.9
Westinghouse Non-Proprietary Class 3 1.5-, 2-, 3-, 4-, 6-, 8.5-, 8.75- and 9-inch diameters at a core power of 36Q0 MWt. The analysis performed at 3304 MWt resulted in the limiting PCT of 1722°F calculated at BOL for the 3.5-inch case and a maximum local transient oxidation of 5.24% calculated at the limiting time-in-life of 20,000 MWD/MTU for the 3.0-inch case. The analysis performed at 3600 MWt resulted in the limiting PCT of 169P1 0 F and a maximum local transient oxidation of 3.98% calculated at BOL for the 8.75-inch case. Note: The analysis performed at the 3304 MWt core power is applicable to core power up to and including 3315 MWt (3304 MWt plus 0.34% uncertainty) with the HHSI cross-tie isolated and the RHR cross-tie valve(s) open during the injection phase. The analysis performed at the 3600 MWt core power is applicable to core power up to and including 3612 MWt (3600 MWt plus 0.34% uncertainty) with both the HHSI and RHR cross-tie valve(s) open during the injection phase.
The analyses presented herein show that the accumulator and SI subsystems of the ECCS, together with the heat removal capability of the steam generators, provide sufficient core heat removal capability to maintain the calculated PCT for SBLOCA below the required limit of 10 CFR 50.46 (Reference 1).
Furthermore, the analyses show that the local cladding oxidation and core wide average oxidation, including consideration of pre-existing and post-LOCA oxidation, and cladding outside and post-rupture inside oxidation, are less than the 10 CFR 50.46 (Reference 1) limits. Note that the core wide average oxidation results illustrate that the total hydrogen generation is less than 1%.
Table 16 provides the summary of the results for the D. C. Cook Unit 2 SBLOCA analyses including PCT, maximum local transient oxidation and total hydrogen generation.
6 REFERENCES
- 1. "Acceptance Criteria for Emergency Core Cooling Systems for Light-Water Nuclear Power Reactors," 10 CFR 50.46 and Appendix K of 10 CFR 50, Federal Register, Volume 39, Number 3, January 1974, as amended in Federal Register, Volume 53, September 1988.
- 2. Meyer, P. E., "NOTRUMP - A Nodal Transient Small Break and General Network Code,"
WCAP-10079-P-A, (proprietary) and WCAP-10080-NP-A (non-proprietary), August 1985.
- 3. Lee, N. et al., "Westinghouse Small Break ECCS Evaluation Model Using the NOTRUMP Code," WCAP-10054-P-A (proprietary) and WCAP-10081-NP-A (non-proprietary),
August 1985.
- 4. Thompson, C. D. et al., "Addendum to the Westinghouse Small Break ECCS Evaluation Model Using the NOTRUMP Code: Safety Injection into the Broken Loop and COSI Condensation Model," WCAP-10054-P-A, Addendum 2, Rev. I (proprietary), July 1997.
- 5. "Generic Evaluation of Feedwater Transients and Small Break Loss-of-Coolant Accidents in Westinghouse - Designed Operating Plant," NUREG-0611, January 1980.
- 6. Rupprecht, S. D. et al., "Westinghouse Small Break LOCA ECCS Evaluation Model Generic Study with the NOTRUMP Code," WCAP-1 1145-P-A (proprietary), October 1986.
10
Westinghouse Non-Proprietary Class 3 Table 1 Input Parameters Used in the SBLOCA Analysis Input Parameter 3304 MWt Analysis 3600 MWt Analysis Core Rated Thermal Power- 100% 3304 MWt 3600 MWt Calorimetric Uncertainty, % 0.34 0.34 Fuel Type 17x17 Vantage 5 Fuel 17x17 Vantage 5 Fuel Total Core Peaking Factor, FQ 2.451 2.32 Hot Channel Enthalpy Rise Factor, FAH 1.667 1.62 Hot Assembly Average Power Factor, PHA 1.484 1.46 Maximum Axial Offset, % 13 13 Initial RCS Loop Flow, gpm/loop 88,500 88,500 Initial Vessel Tavg, 0 F 578.2(1) 578.2(')
Initial Pressurizer Pressure (plus uncertainties), psia 2312.6(2) 2312.6(2)
Reactor Coolant Pump Type 93A 93A Pressurizer Low-Pressure Reactor Trip Setpoint, psia 1860 1860 Reactor Trip Signal Processing Time, seconds 2.0 2.0 Rod Drop Time, seconds 2.7 2.7 Auxiliary Feedwater Temperature (Maximum), 'F 120 120 AFW Flow (Minimum) to all 4 Steam Generators, gpm 750 750 AFW Flow Delay Time (Maximum), seconds 80 80 AFW Actuation Signal Reactor Trip/Low Reactor Trip/Low Pressurizer Pressure Pressurizer Pressure Maximum AFW Piping Purge Volume, ft3 78 78 Steam Generator Tube Plugging (Maximum), % 10 10 Maximum MFW Isolation, seconds 8 8 MFW Isolation Signal Safety Injection Safety Injection Actuation Actuation Steam Generator Secondary Water Mass, lbm/SG 101,425 98,352 Containment Spray Flowrate for 2 Pumps, gpm 7,400 7,400 RWST Deliverable Volume (Minimum), gallons 280,000 280,000 Notes:
(1) Analysis supports operation over the range of nominal full-power Tavg values of 547.6'F - 578.1 0 F with Tavg uncertainty range of -4.1 'F/-5.6°F.
(2) Analysis supports operation at nominal initial pressurizer pressure (without uncertainties) of 2100 psia and 2250 psia.
11
Westinghouse Non-Proprietary Class 3 Table 1 (continued)
Input Parameters Used in the SBLOCA Analysis Input Parameter 3304 MWt Analysis 3600 MWt Analysis SI Temp at Cold Leg Recirculation Time (Maximum), 'F 190 190 ECCS Configuration 1 CHG pump, 1 HHSI 1 CHG pump, 1 HHSI pump, 1 RHR pump - pump, 1 RHR pump -
faulted loop injects to faulted loop injects to RCS pressure (1.5- RCS pressure (1.5-inch through 6-inch inch through 8.5-inch breaks) breaks) 1 CHG pump, 1 1 CHG pump, 1 HHSI HHSI pump, 1 RHR pump, 1 RHR pump -
pump -no RHR/HHSI no RHR/HHSI in the in the faulted loop faulted loop because because the break is the break is postulated postulated along the along the accumulator accumulator line, line, faulted loop faulted loop CHG CHG flow injects to flow injects to RCS RCS pressure (> 8.75-pressure (8.75-inch inch break) break)
Cross Tie Valve Position(s) - Injection Phase HHSI Isolated and Both HHSI and RHR RHR Open Open Cross Tie Valve Position(s) - Recirculation Phase Both HHSI and RHR Both HHSI and RHR Isolated Isolated ECCS Water Temperature (Maximum), 'F 120 120 Pressurizer Low-Pressure Safety Injection Setpoint, psia 1715 1715 SI Flow Delay Time, seconds 54 54 ECCS Flow vs. Pressure (Injection Phase) See Tables 2 and 3 See Tables 6 and 7 ECCS Flow vs. Pressure (Recirculation Phase) See Tables 4 and 5 See Tables 8 and 9 Initial Accumulator Water/Gas Temperature, 'F 130 130 3
Initial Nominal Accumulator Water Volume, ft 946 946 Minimum Accumulator Pressure, psia 600 600 12
Westinghouse Non-Proprietary Class 3 Table 2 (3304 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 6-inch breaks)
RCS Pressure Broken Loop Intact Loops (lbm/sec)
(psia) (lbm/sec)
Loop 1 Loop 2 Loop 3 Loop 4 14.7 176.81 144.32 156.72 145.27 74.7 147.24 118.98 130.47 119.71 94.7 134.89 108.39 119.50 109.03 114.7 120.73 96.27 106.94 96.80 134.7 102.60 80.75 90.84 81.15 154.7 76.13 58.23 67.35 58.43 174.7(') 35.66 11.89 31.42 11.70 214.7 35.15 11.78 30.98 11.59 314.7 33.76 11.49 29.75 11.32 414.7 32.32 11.21 28.47 11.03 514.7 30.82 10.92 27.15 10.74 614.7 29.25 10.61 25.75 10.45 714.7 27.59 10.31 24.30 10.16 814.7 25.84 10.01 22.73 9.86 914.7 23.91 9.68 21.03 9.54 1014.7 21.58 9.34 18.98 9.20 1114.7 18.92 8.99 16.61 8.85 1214.7 15.63 8.63 13.70 8.50 1314.7 10.63 8.26 9.28 8.14 1414.7(2) 9.03 7.89 7.89 7.77 1514.7 8.59 7.51 7.49 7.38 1614.7 8.10 7.07 .7.07 6.96 1714.7 7.58 6.61 6.61 6.52 1814.7 7.05 6.16 6.15 6.06 1914.7 5.32 4.65 4.63 4.56 2014.7 4.67 4.08 4.08 4.03 2114.7 3.95 3.45 3.44 3.40 13
Westinghouse Non-Proprietary Class 3 Table 2 (3304 MWt) - (continued)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 6-inch breaks)
RCS Pressure Broken Loop Intact Loops (lbm/sec)
(psia) (lbm/sec)
Loop 1 Loop 2 Loop,3 Loop 4 2214.7 3.05 2.67 2.67 2.63 2314.7(3) 0.00 0.00 0.00 0.00 2414.7 0.00 0.00 0.00 0.00 Notes:
(1) RHR cut-in pressure (2) HHSI cut-in pressure (3) CHG cut-in pressure 14
Westinghouse Non-Proprietary Class 3 Table 3 (3304 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump -no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure - 8.75-inch break)
RCS Pressure Broken Loop (lbm/sec) Intact Loops (lbm/sec)
(psia)
Loop 1 - CHG Loop 1 - Loop 2 Loop 3 Loop 4 RHR/HHSI 14.7 14.1 162.7 144.3 156.7 145.3 34.7 14.1 230.2 131.4 91.0 132.2 54.7() 14.0 299.4 120.8 12.2 121.6 74.7 13.9 318.8 98.7 12.2 99.2 94.7 13.9 339.6 73.3 12.1 73.7 114.7 13.8 362.9 42.1 12.0 42.2 134.7(2) 13.7 383.3 12.0 12.0 11.8 154.7 13.7 383.3 11.9 11.9 11.8 214.7 13.5 383.3 11.8 11.8 11.6 314.7 13.2 383.3 11.5 11.5 11.3 414.7 12.8 383.3 11.2 11.2 11.0 514.7 12.5 383.3 10.9 10.9 10.7 614.7 12.2 383.3 10.6 10.6 10.4 714.7 11.8 383.3 10.3 10.3 10.2 814.7 11.5 383.3 10.0 10.0 9.9 914.7 11.1 383.3 9.7 9.7 9.5 1014.7 10.7 383.3 9.3 9.3 9.2 1114.7 10.3 383.3 9.0 9.0 8.9 1214.7 9.9 383.3 8.6 8.6 8.5 1314.7 9.5 383.3 8.3 8.3 8.1 1414.7 9.0 383.3 7.9 7.9 7.8 1514.7 8.6 383.3 7.5 7.5 7.4
'1614.7 8.1 383.3 7.1 7.1 7.0 1714.7 7.6 383.3 6.6 6.6 6.5 1814.7 7.1 383.3 6.2 6.1 6.1 1914.7 5.3 383.3 4.6 4.6 4.6 2014.7 4.7 383.3 4.1 4.1 4.0 15
Westinghouse Non-Proprietary Class 3 Table 3 (3304 MWt) - (continued)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump -no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure - 8.75-inch break)
RCS Pressure Broken Loop (lbm/sec) Intact Loops (lbm/sec)
(psia)
Loop 1 - CHG Loop 1 - Loop 2 Loop 3 Loop 4 RHR/HHSI 2114.7 3.9 383.3 3.5 3.4 3.4 2214.7 3.1 383.3 2.7 2.7 2.6 2314.7(3) 0.0 383.3 0.0 0.0 0.0 Notes:
(1) HHSI cut-in pressure (2) RHR cut-in pressure (3) CHG cut-in pressure 16
Westinghouse Non-Proprietary Class 3 Table 4 (3304 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Recirculation Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 6-inch breaks)
RCS Pressure Broken Loop Intact Loops (lbm/sec)
(psia) (lbm/sec)
Loop 1 Loop 2 Loop 3 Loop 4 14.7 228.7 12.3 202.8 12.1 34.7 213.8 12.3 189.6 12.1 54.7 197.9 12.2 175.4 12.0 74.7 180.3 12.2 159.8 12.0 94.7 161.0 12.1 142.6 11.9 114.7 137.0 12.1 121.4 11.9 134.7 106.1 12.0 93.9 11.8 154.7 55.5 11.9 49.0 11.8 174.7 37.7 11.9 33.2 11.7 194.71' 37.4 11.8 33.0 11.6 214.7 37.2 11.8 32.8 11.6 Notes:
(1) RHR cut-in pressure 17
Westinghouse Non-Proprietary Class 3 Table 5 (3304 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Recirculation Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure - 8.75-inch break)
RCS Pressure Broken Loop (Ibm/sec) Intact Loops (Ibm/sec)
(psia)
Loop 1 - CHG Loop 1 - Loop 2 Loop 3 Loop 4 RHR/HHSI 14.7 14.1 214.6 12.3 202.8 12.1 34.7 14.1 260.3 12.3 142.2 12.1 54.7 14.0 311.3 12.2 70.2 12.0 74.7(1'2) 13.9 350.2 12.2 12.2 12.0 94.7 13.9 350.3 12.1 12.1 11.9 114.7 13.8 350.4 12.1 12.0 11.9 Notes:
(1) HHSI cut-in pressure (2) RHR cut-in pressure 18
Westinghouse Non-Proprietary Class 3 Table 6 (3600 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 8=-inc~h hreak*
RCS Pressure Broken Loop Intact Loops (lbm/sec)
(psia) (lbm/sec)
Loop 1 Loop 2 Loop 3 Loop 4 14.7 177.8 155.5 157.6 156.5 34.7 169.2 148.1 150.0 149.0 54.7 159.3 139.5 141.2 140.4 74.7 148.1 129.8 131.2 130.6 94.7 135.8 119.1 120.3 119.8 114.7 121.5 106.7 107.7 107.4 134.7 103.3 91.0 91.5 91.5 154.7 77.0 68.1 68.2 68.4 174.7(') 31.3 28.5 27.6 28.4 194.7 31.1 28.3 27.4 28.2 214.7 30.9 28.1 27.2 28.0 234.7 30.6 27.9 . 26.9 27.8 254.7 30.4 27.6 26.7 27.6 274.7 30.1 27.4 26.5 27.4 294.7 29.9 27.2 26.3. 27.1 314.7 29.7 27.0 26.1 26.9 414.7 28.4 25.8 25.0 25.8 514.7 27.2 24.7 23.9 24.6 614.7 25.8 23.4 22.7 23.4 714.7 24.4 22.1 21.5 22.1 814.7 23.0 20.8 20.2 20.8 914.7 21.4 19.3 18.8 19.3 1014.7 19.5 17.5 17.1 17.5 1114.7 17.4 15.6 15.2 15.5 1214.7 14.4 12.9 12.6 12.8 1314.7 10.1 8.8 8.8 8.7 1414.7(2) 9.0 7.9 7.9 7.8 19
Westinghouse Non-Proprietary Class 3 Table 6 (3600 MWt) - (continued)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 8.5-inch breaks)
RCS Pressure Broken Loop Intact Loops (lbm/sec)
(psia) (lbm/sec)
Loop 1 Loop 2 Loop 3 Loop 4 1514.7 8.6 7.5 7.5 7.4 1614.7 8.1 7.1 7.1 7.0 1714.7 7.6 6.6 6.6 6.5 1814.7 7.1 6.2 6.1 6.1 1914.7 5.3 4.6 4.6 4.6 2014.7 4.7 4.1 4.1 4.0 2114.7 3.9 3.5 3.4 3.4 2214.7 3.1 2.7 2.7 2.6 2314.7(3) 0.0 0.0 0.0 0.0 2414.7 0.0 0.0 0.0 0.0 Notes:
(1) RHR cut-in pressure (2) HHSI cut-in pressure (3) CHG cut-in pressure 20
Westinghouse Non-Proprietary Class 3 Table 7 (3600 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure - >_8.75-inch break)
RCS Pressure Broken Loop (lbm/sec) Intact Loops (lbm/sec)
(psia)
Loop 1 - CHG Loop 1 - Loop 2 Loop 3 Loop 4 RHR/HHSI 14.7 14.1 163.7 155.5 157.6 156.5 34.7 14.1 230.7 142.6 92.1 143.5 54.7 14.0 300.3 132.0 12.2 132.9 74.7 13.9 319.2 110.1 12.2 110.7 94.7 13.9 339.5 85.1 12.1 85.5 114.7 13.8 362.1 54.4 12.0 54.6 134.7") 13.7 379.3 28.8 12.0 28.8 154.7 13.7 379.5 28.6 11.9 28.5 174.7 13.6 379.6 28.3 11.9 28.2 194.7 13.6 379.6 28.0 11.8 28.0 214.7 13.5 379.7 27.7 11.8 27.7 234.7 13.4 379.8 27.4 11.7 27.4 254.7 13.4 379.8 27.2 11.7 27.1 274.7 13.3 379.9 26.9 11.6 26.8 294.7 13.2 379.9 26.6 11.5 26.5 314.7 13.2 380.0 26.3 11.5 26.2 414.7 12.8 380.3 24.7 11.2 24.7 514.7 12.5 380.6 23.1 10.9 23.1 614.7 12.2 386.8 20.8 10.6 20.7 714.7 11.8 387.8 17.6 10.3 17.6 814.7 11.5 388.9 13.9 10.0 13.8 914.7(2) 11.1 390.1 9.7 9.7 9.5 1014.7 10.7 390.1 9.3 9.3 9.2 1114.7 10.3 390.2 9.0 9.0 8.9 1214.7 9.9 390.2 8.6 8.6 8.5 1314.7 9.5 390.2 8.3 8.3 8.1 21
Westinghouse Non-Proprietary Class 3 Table 7(3600 MWt) - (continued)
Safety Injection Flows Used in the SBLOCA Analysis - Injection Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure - Ž_8.75-inch break)
RCS Pressure Broken Loop (lbm/sec) Intact Loops (lbm/sec)
(psia)
Loop 1 - CHG Loop 1 - Loop 2 Loop 3 Loop 4 RHR/HHSI 1414.7 9.0 390.2 7.9 7.9 7.8 1514.7 8.6 390.2 7.5 7.5 7.4 1614.7 8.1 390.2 7.1 7.1 7.0 1714.7 7.6 390.2 6.6 6.6 6.5 1814.7 7.1 390.2 6.2 6.1 6.1 1914.7 5.3 390.2 4.6 4.6 4.6 2014.7 4.7 390.2 4.1 4.1 4.0 2114.7 3.9 390.2 3.5 3.4 3.4 2214.7 3.1 390.2 2.7 2.7 2.6 2314.7"') 0.0 390.2 0.0 0.0 0.0 2414.7 0.0 390.2 0.0 0.0 0.0 Notes:
(1) RHR cut-in pressure (2) HHSI cut-in pressure (3) CHG cut-in pressure 22
Westinghouse Non-Proprietary Class 3 Table 8 (3600 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Recirculation Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 8.5-inch breaks)
RCS Pressure Broken Loop Intact Loops (lbm/sec)
(psia) (lbm/sec)
Loop 1 Loop 2 Loop 3 Loop 4 14.7 230.1 12.5 203.0 12.5 34.7 215.2 12.5 189.8 12.5 54.7 199.3 12.4 175.6 12.4 74.7 181.8 12.4 160.1 12.4 94.7 162.4 12.4 142.9 12.4 114.7 138.5 12.3 121.7 12.3 134.7 107.6 12.3 94.3 12.3 154.7 57.1 12.3 49.4 12.3 174.7 39.2 12.2 33.6 12.2 194.7(1) 39.0 12.2 33.3 12.2 214.7 38.7 12.1 33.1 12.1 234.7 38.4 12.1 32.9 12.1 254.7 38.2 12.0 32.7 12.0 274.7 37.9 12.0 32.4 12.0 294.7 37.6 11.9 32.2 11.9 314.7 37.4 11.9 32.0 11.9 414.7 36.0 11.6 30.7 11.6 514.7 34.5 11.3 29.5 11.3 614.7 33.0 10.9 28.1 10.9 714.7 31.4 10.6 26.8 10.6 814.7 29.7 10.3 25.3 10.3 914.7 27.7 10.0 23.6 10.0 1014.7 25.7 9.6 21.8 9.6 1114.7 23.4 9.3 19.8 9.3 1214.7 20.9 9.0 .17.6 9.0 Notes:
(1) RHR cut-in pressure 23
Westinghouse Non-Proprietary Class 3 Table 9 (3600 MWt)
Safety Injection Flows Used in the SBLOCA Analysis - Recirculation Phase (1 CHG pump, 1 HHSI pump, 1 RHR pump - no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure - > 8.75-inch break)
RCS Pressure Broken Loop (lbm/sec) Intact Loops (lbm/sec)
(psia)
Loop 1 - CHG Loop 1 - Loop 2 Loop 3 Loop 4 RHRIHHSI 14.7 15.5 214.6 12.5 203.0 12.5 34.7 15.5 260.3 12.5 142.4 12.5 54.7 15.4 311.3 12.4 70.5 12.4 74.7(1'2) 15.4 350.2 12.4 12.4 12.4 94.7 15.4 350.3 12.4 12.4 12.4 114.7 15.3 350.4 12.3 12.3 12.3 Notes:
(1) HHSI cut-in pressure (2) RHR cut-in pressure 24
Westinghouse Non-Proprietary Class 3 Table 10 (3304 MWt)
SBLOCTA BOL Results Break Size (in) 2 2.5 2.75 3 3.25 3.5 3.75 4 8.75 0
PCT ( F) 1457.2 1571.1 1607.1 1709.0 1681.6 1722.0 1667.0 1522.8 1261.9 PCT Time (s) 3752.2 3172.9 2148.0 2025.2 1592.8 1312.4 982.9 883.3 3448.9 PCT Elevation (ft) 11.75 11.75 11.50 11.75 11.75 11.75 11.25 11.25 11.50 Max. Local ZrO 2 (%) 0.97 1.39 2.46 2.81 1.93 1.96 1.38 0.58 0.12 Max. Local ZrO 2 Elev. (ft) 11.75 11.75 11.75 11.75 11.75 11.75 11.50 11.50 11.50 Hot Rod Axial Average 0.13 0.18 0.32 0.37 0.27 0.29 0.22 0.09 0.01 ZrO2 ()1 Notes:
(1) The hot rod axial average ZrO2 conservatively represents the core wide average oxidation, since the core wide average ZrO2 thickness will always be less than the corresponding hot rod axial average ZrO 2 thickness.
Table 11 (3304 MWt)
SBLOCTA Limiting Results Limiting PCT Max Transient (3.5-inch) Oxidation (3-inch)
Time-in-Life (MWD/MTU) BOL 20,000 PCT (0 F) 1722.0 1692.8 PCT Time (s) 1312.4 2025.2 PCT Elevation (ft) 11.75 12.00 Hot Rod Burst Time (s) N/A 1912 Hot Rod Burst Elevation (ft) N/A 11.75 Max. Local Transient ZrO 2 (%) 1.96 5.24 Max. Local Transient ZrO 2 Elev. (ft) 11.75 11.75 Hot Rod Axial Average ZrO 2 (%)(1) 0.29 0.25 Notes:
(1) The hot rod axial average ZrO2 conservatively represents the core wide average oxidation, since the core wide average ZrO 2 thickness will always be less than the corresponding hot rod axial average ZrO 2 thickness.
25
Westinghouse Non-Proprietary Class 3 Table 12 (3600 MWt)
SBLOCTA BOL Results Break Size (in) 2.0 3.0 4.0 8.75 9.0 PCT (0 F) 1421.9 1176.5 1273.7 1691.3 1260.3 PCT Time (s) 4426.0 1603.1 971.5 3412.3 3364.1 PCT Elevation (ft) 11.75 11.25 11.25 12.00 11.75 Max. Local ZrO 2 (%) 0.85 0.11 0.11 3.98 0.15 Max. Local ZrO 2 Elev. (ft) 11.75 11.50 11.25 11.75 11.50 Hot Rod Axial Average 0.11 0.02 0.02 0.25 0.02 ZrO2 (%)(I)
Notes:
(1) The hot rod axial average ZrO2 conservatively represents the core wide average oxidation, since the core wide average ZrO2 thickness will always be less than the corresponding hot rod axial average ZrO 2 thickness.
Table 13 (3600 MWt)
SBLOCTA Limiting Results from the 8.75-inch Time-in-Life Study Time-in-Life (MWD/MTU) BOL PCT (0 F) 1691.3 PCT Time (s) 3412.3 PCT Elevation (ft) 12.00 Hot Rod Burst Time (s) 3281.6 Hot Rod Burst Elevation (ft) 11.75 Max. Local Transient ZrO2 (%) 3.98 Max. Local Transient ZrO 2 Elev. (ft) 11.75 Hot Rod Axial Average ZrO 2 (%)(1) 0.25 Notes:
(1) The hot rod axial average ZrO2 conservatively represents the core wide average oxidation, since the core wide average ZrO 2 thickness will always be less than the corresponding hot rod axial average ZrO 2 thickness.
26
Westinghouse Non-Proprietary Class 3 Table 14 (3304 MWt)
Time Sequence of Events 2.75- 3.25- 3.75-Event Time 1.5-inch 2-inch 2.5-inch inch 3-inch inch 3.5-inch inch 4-inch 6-inch 8.75-inch Break Initiation (s) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Reactor Trip Signal (s) 84.98 44.90 27.41 22.46 18.87 16.11 13.93 12.23 10.84 5.94 4.51 S-Signal (s) 104.07 57.65 37.38 31.41 26.99 23.48 20.84 18.53 16.28 8.35 6.77 SI Flow Delivered (1),(s) 158.07 111.65 91.38 85.41 80.99 77.48 74.84 72.53 70.28 62.35 60.77 Loop Seal Clearing (2) (s) 2273 1227 783 651 .612 459 398 363 309 151 30 Core Uncovery (4) (s) N/A 1646 1386 1056 912 872 745 610 541 N/A 972/2678 Accumulator Injection (s) N/A N/A 3169 2124 1695 1386 1104 898 800 349 169(31 RWST Volume Delivered (5) (s) 2174.81 2167.63 2155.55 2147.64 2140.24 2133.96 2127.95 2122.70 2119.07 2093.01 1571.52 PCT Time (BOL) (s) N/A 3752.2 3172.9 2148.0 2025.2 1592.8 1312.4 982.9 883.3 N/A 3448.9 Core Recovery (4) (s) N/A 9843 5907 6200 5823 5347 4745 4658 4325 N/A 1207/4756 Notes:
(1) SI is assumed to begin 54.0 seconds (SI delay time) after the S-Signal.
(2) Loop seal clearing is assumed to occur when the steam flow through the broken loop, loop seal is sustained above I ibm/s.
(3) For the 8.75-inch, accumulator injection begins for Loops 2-4 only; Loop 1 (broken loop) accumulator line is the location of the break and assumed to spill to containment.
(4) The latest point of sustained core uncovery/recovery is reported. There are two uncovery periods for the 8.75-inch break.
(5) The analysis assumes minimum usable RWST volume (280,000 gal) delivered via ECCS injection and containment spray before the low level RWST water level signal for switchover to cold leg recirculation is reached.
27
Westinghouse Non-Proprietary Class 3 Table 15 (3600 MWt)
Time Sequence of Events 8.75-Event Time 1.5-inch 2-inch 3-inch 4-inch 6-inch 8.5-inch inch 9.0-inch Break Initiation (s) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Reactor Trip Signal (s) 89.72 46.48 19.17 11.02 6.09 4.84 4.83 4.79 S-Signal (s) 108.11 59.03 27.57 17.71 9.65 7.72 7.66 7.58 SI Flow Delivered (1),(s) 162.11 113.03 81.57 71.71 63.65 61.72 61.66 61.58 Loop Seal Clearing (2)(s) 2630 1422 551 310 146 31 26 24 Core Uncovery (4)(s) N/A 1726 877 602 N/A N/A 2339 2466 Accumulator Injection (s) N/A N/A 1800 864 352 177(') 168(') 157(')
RWST Volume Delivered (5) (s) 2161.88 -2151.71 2115.48 2088.59 2052.49 1780.19 1565.20. 1553.03 PCT Time (BOL) (s) N/A 4426.0 1603.1 971.5 N/A N/A 3412.3 3364.1 Core Recovery (4) (s) N/A N/A(61 N/A(6) 2830 N/A N/A 5859 N/A(6)
Notes:
(1) SI is assumed to begin 54.0 seconds (SI delay time) after the S-Signal.
(2) Loop seal clearing is assumed to occur when the steam flow through the broken loop, loop seal is sustained above 1 lbm/s.
(3) For breaks ? 8.75-inch (and 8.5-inch break), accumulator injection begins for Loops 2-4 only; Loop 1 (broken loop) accumulator line is the location of the break and assumed to spill to containment.
(4) The latest point of sustained core uncovery/recovery is reported.
(5) The analysis assumes minimum usable RWST volume (280,000 gal) delivered via ECCS injection and containment spray before the low level RWST water level signal for switchover to cold leg recirculation is reached.
(6) The run was successfully terminated per the NOTRUMP transient termination criteria described in Section 4.1.4 of the report text.
28
Westinghouse Non-Proprietary Class 3 Table 16 SBLOCA Results Summary 3304 MWt Analysis 3600 MWt Analysis Peak Cladding Temperature ('F) 1722.0 1691.3 Maximum Local Transient Oxidation (%) 5.24 3.98 Total Hydrogen Generation (%) <1 <1 29
Westinghouse Non-Proprietary Class 3 8 . . . . . .
I- "
0 2 4 6 8 10 12 Elevation (ft)
Figure 1 Small Break Hot Rod Power Shape (3304 MWt) 30
Westinghouse Non-Proprietary Class 3 0
4-
.. I 0 2 4 6 8 10 12 Elevation (ft)
Figure 2 Small Break Hot Rod Power Shape (3600 MWt) 31
Westinghouse Non-Proprietary Class 3 Ll L2 Broken Intact Loop)
Loop)
L3 Intact Loop)
L4 Intact Loop 200 150" . 150................................
. I.........
af 100-0 Ul) 0~
0 500 1000 1500 2000 2500 Pressure (psia)
Figure 3 SBLOCA Safety Injection Flows - Injection Phase (3304 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 6-inch breaks) 32
Westinghouse Non-Proprietary Class 3 L1 Broken Loop - CHG Flow)
L1 Broken Loop - HHSI/RHR Flow)
L2 L3 Intact Intact LLoop o op)
L4 Intact Loo p)
CI)
E (o
0 MI 0 500 1000 1500 2000 2500 Pressure (psia)
Figure 4 SBLOCA Safety Injection Flows - Injection Phase (3304 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump -no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure -
8.75-inch break) 33
Westinghouse Non-Proprietary Class 3 Li 1Broken Loop)
L2 Intact Loop)
L3 1Intact L4 Intact Loop)
LZDU 200- . ..... .... .. . ... ..
U)
E 1501 '
C3 0
~ ~~
.~~~~~~ ~ .S 0 100"1 M) 03 50-U 1 I 2 0 50 100 150 200 250 Pressure (psia)
Figure 5 SBLOCA Safety Injection Flows - Recirculation Phase (3304 MWt)
(1 CHG pump, 1 HIRSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 6-inch breaks) 34
Westinghouse Non-Proprietary Class 3 L1 Broken Loop - CHG FIow)
L1 Broken Loop - HHSI/RHR Flow)
L2 Intact Loopo)
L3 Intact Lo op L4 Intact
'tUU 350-300-250-K.
200- KS K'
S K, K. . .
0 150- .... ......... ." .......
M) 100-50-I I I I I . I I I I I I I I . i I
"-4 U
0 20 40 60 80 100 120 Pressure (psia)
Figure 6 SBLOCA Safety Injection Flows - Recirculation Phase (3304 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump -no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure -
8.75-inch break) 35
Westinghouse Non-Proprietary Class 3 Li ( Broken Loop)
L2 Intact Loop)
L3 Intact L4 Intact Loop)
Of U)
M) 0 500 1000 1500 2000 2500 Pressure (psia)
Figure 7 SBLOCA Safety Injection Flows - Injection Phase (3600 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 8.5-inch breaks) 36
Westinghouse Non-Proprietary Class 3 L1 Broken Loop - CHG Flow)
L1 Broken Loop - HHSI/RHR Flow)
L2 Intact Loopp L3 Intact Loopp L4 Intact Loopp 4UU -- ------- -- ---
300 -
U)
E
-o t_) 200 0 /
03 U) A.
0 500 1000 1500 2000 2500 Pressure (psia)
Figure 8 SBLOCA Safety Injection Flows - Injection Phase (3600 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump -no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure -
> 8.75-inch break) 37
Westinghouse Non-Proprietary Class 3 Li Broken Loop)
L2 Intact Loop)
LLoop) o op L3 Intact L4 Intact F'
250-200-(n E . .a
- 150-100" 0
50-A.'.
0 200 1000 1200 1400 Pressure (psia)
Figure 9 SBLOCA Safety Injection Flows - Recirculation Phase (3600 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump - faulted loop injects to RCS pressure - 1.5-inch through 8.5-inch breaks) 38
Westinghouse Non-Proprietary Class 3 L1 Loop - CHG Flow)
L1 Broken Loop - HHSI/RHR Flow)
L2 Intact Broken L°oop)
L3 Intact Loopp L4 Intact Loopp RAn-.
.t'Ju 350-300-C,)
E 250- . . . . . . . . . . . .
-D K
200- KS KS 0
. =/ .
(n)
En, 150- \K
\K 100- \KS 50-N n-U 0 20 40 60 80 100 120 Pressure (psia)
Figure 10 SBLOCA Safety Injection Flows - Recirculation Phase (3600 MWt)
(1 CHG pump, 1 HHSI pump, 1 RHR pump -no RHR/HHSI in the faulted loop because the break is postulated along the accumulator line, faulted loop CHG flow injects to RCS pressure -
> 8.75-inch break) 39
Westinghouse Non-Proprietary Class 3 CORE PRESSURE, CORE FLOW, MIXTURE LEVEL, AND FUEL ROD POWER N HISTORY 0 O<TIME<CORE COVERED L
T 0 R C U T M A P
Figure 11 Code Interface Description for Small Break Model 40
Westinghouse Non-Proprietary Class 3
.) 1500 10 0 . . . . . . . . . . .. . . .
Cl-)
5~
000 0 I I I I , I I I I I I I I , I I I I , I I I I , I I I I 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 12 3.5-inch Break (3304 MWt)
RCS Pressure 41
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft X4 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 13 3.5-inch Break (3304 MWt)
Core Mixture Level 42
Westinghouse Non-Proprietary Class 3 10 00- ............................................
800 . ........ ............... . ................................
600-400 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 14 3.5-inch Break (3304 MWt)
Core Exit Vapor Temperature 43
Westinghouse Non-Proprietary Class 3 L1 1Broken L2 Intact Loop)
L3 Intact Loop)
L4 1Intact Loop) 44rfl-I JJV 110011-1050-1000-1 Cn Cn 950- ........................
0l 9001 ............................... ..................
850- ...........................
I I I I I I I I I I I I I I I I I I I I I I I I aJnn-t Uvv 1 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 15 3.5-inch Break (3304 MWt)
Broken and Intact Loops Secondary Pressures 44
Westinghouse Non-Proprietary Class 3 160.
140- .14.0 120o c 8. ......
E 10 60 - . . ...
0 M . .. ... .. ... ....
40-. .
20.
0 I I I I*** I I I I*II I I t I I ! I 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 16 3.5-inch Break (3304 MWt)
Break Vapor Flow Rate 45
Westinghouse Non-Proprietary Class 3 U)..
E 10 0 0 . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
U).
500-0 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 17 3.5-inch Break (3304 MWt)
Break Liquid Flow Rate 46
Westinghouse Non-Proprietary Class 3 Ll 1Broken Loop)
L2 Intact Loop L3 Intact Loop L4 Intact Loop ILU 100- .......... . . . . . . . . . . . . . . . . . . .
80-1 ................
E 601 ' .............. . . . . . . . . . . . . . . . . . .
0 U)
M) 401 ................ . . . . . . . . . . . . . . . . . . .
201 .........
A A ..
h1 I~L rJ, I I I 1 U
0 1000 2000 3000 A 4000 5000 6000 Time (s)
Figure 18 3.5-inch Break (3304 MWt)
Broken and Intact Loops Accumulator Flow Rates 47
Westinghouse Non-Proprietary Class 3 Li IBroken Loop )
- - - -- L2 Intact Loop L3 Intact Loop
"-L4 Intact Loop 35-30-. . . . . . . . . . . . . . . . . . . . . . . . . . .
2 0. . .. . . . . . . . . . . . . . ...... . . . . . . . .
E 0 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
O0 5 C,)
M 0- .... . .%
5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
0 l l Ill l l l lIl l l l 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 19 3.5-inch Break (3304 MWt)
Broken and Intact Loops Pumped Safety Injection Flow Rates 48
Westinghouse Non-Proprietary Class 3 La..S1200-.
S1000-8 0 .. . .
600 -
400 I 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 20 3.5-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 49
Westinghouse Non-Proprietary Class 3 1200" E 1000" 80 0 . . . . .
800 400-II 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 21 3.5-inch Break (3304 MWt)
Hot Spot Fluid Temperature at PCT Elevation (11.75 ft) 50
Westinghouse Non-Proprietary Class 3 5
10 4
10 10 CO 0
2 F.- 210 10 U) 2 (10 t--
al) 10- ............
0 I I I 10 1 I 4 0 1200 2400 3600 4800 6000 Time (s)
Figure 22 3.5-inch Break (3304 MWt)
Rod Film Heat Transfer Coefficient at PCT Elevation (11.75 ft) 51
Westinghouse Non-Proprietary Class 3 o 1800.
1400" 1200-1000I I I , I I , ,
1000-0 1000 2000 3000 4000 5000 Time (s)
Figure 23 1.5-inch Break (3304 MWt)
RCS Pressure 52
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft (D
-4 X) 22 0 1000 2000 3000 4000 5000 Time (s)
Figure 24 1.5-inch Break (3304 MWt)
Core Mixture Level 53
Westinghouse Non-Proprietary Class 3 I UUV S1600-1400-1200 . 14. .0. .. :. .. . .. .. . . .. . . . . .. . . . . .. . . .. .. .. . .. . . .. .. . . ... .. .. .. ..
1000- ,
800*
0 2000 4000 6000 8000 10000 12000 Time (s)
Figure 25 2-inch Break (3304 MWt)
RCS Pressure 54
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft Q>
-4 X) m 0 2000 4000 6000 8000 10000 12000 Time (s)
Figure 26 2-inch Break (3304 MWt)
Core Mixture Level 55 '
Westinghouse Non-Proprietary Class 3 U-C-
E 0 2000 4000 6000 8000 10000 12000 Time (s)
Figure 27 2-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 56
Westinghouse Non-Proprietary Class 3 15 00 . . ... . . . . . . . . . . . . . . . . . . .
03 500-U ).... . ." . . . ." . .
1000-*
0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 28 2.5-inch Break (3304 MWt)
RCS Pressure 57
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft 30,
.?5 25' 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 29 2.5-inch Break (3304 MWt)
Core Mixture Level 58
Westinghouse Non-Proprietary Class 3 LL-6000 . . . . . . . . . . . .. . . . . . .. . . . . . .. . . . . . . .. . . .
000 4~
40I II , I I I I II I* I I I I 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 30 2.5-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 59
Westinghouse Non-Proprietary Class 3 0 . . . . . . . . . . . . . . . . .
1500.
1000 ." . . . . ... .. . . . .. ...
1000 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 31 2.75-inch Break (3304 MWt)
RCS Pressure 60
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft 0) 0 1000 2000 3000 4000 5000 6000 7000 Time. (s)
Figure 32 2.75-inch Break (3304 MWt)
Core Mixture Level 61
Westinghouse Non-Proprietary Class 3 1200-E 1000-800-600 - . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . .. . . .
600 400 I I I*
1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 33 2.75-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.5 ft) 62
. Ix
Westinghouse Non-Proprietary Class 3 1500-50 - . . . . .. . . . . . .
500-0 , I I i i JII I I I I I I I 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 34 3-inch Break (3304 MWt)
RCS Pressure 63
Westinghouse Non-Proprietary Class 3 Core Mixture Level
-- --- Top of Core = 22.0778 ft X4
- 2) 15 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 35 3-inch Break (3304 MWt)
Core Mixture Level 64
Westinghouse Non-Proprietary Class 3 1200 . . . . . . . . . . . .
a.--
CL)
E 1000 ..
800 - . . . . . . . . . . . . . . . . .. . . . . . . . . . .
600 . . . . . . . . . . . . . . . . . . . . . . . . . .-
400 400 I 111111 I I I* II I 11 I I I I1 I I* I I I 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 36 3-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 65
Westinghouse Non-Proprietary Class 3
.2 1500 ... . . . .
"3 oL 101000-0 . . .. . . . .
500.
l*I I I I III I II I lI I I Ii ii I I I I I III U iI I I 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 37 3.25-inch Break (3304 MWt)
RCS Pressure 66
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft XJ
- M 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 38 3.25-inch Break (3304 MWt)
Core Mixture Level 67
Westinghouse Non-Proprietary Class 3
- 1. . . . .
1200 E 0 00. . . . . . .
E 1000 . .....
800 600) . . . . . . . . . . . . . . . . . .
- /
0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 39 3.25-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 68
Westinghouse Non-Proprietary Class 3
.9 1500.
10) 0)
0 1100 2200 3300 4400 5500 Time (s)
Figure 40 3.75-inch Break (3304 MWt)
RCS Pressure 69
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft
'4-0 1100 2200 3300 4400 5500 Time (s)
.Figure 41 3.75-inch Break (3304 MWt)
Core Mixture Level 70
Westinghouse Non-Proprietary Class 3 CL.
H-*
8000 . . . . . . . . . .. . . . . . . .. . .. . .. . . .. . . ..
600 - " . . . . . . . . . . . . . . ....
400.. .- L 0 1100 2200 3300 4400 5500 Time (s)
Figure 42 3.75-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.25 ft) 71
Westinghouse Non-Proprietary Class 3
.9 1500......
. L 15000 . . . . . . . . . . . . . . . . . . . . . . . . . . ..... . . . . . .
a..
0.0 1000 .. . . . . . . . . ' . .
500 - " " " . . . . . . . " "" . . . . ' " ". . . "
11 I I I I
- I I I I
- I I I I
- I I I I*I 0 1000 2000 3000 4000 5000 Time (s)
Figure 43 4-inch Break (3304 MWt)
RCS Pressure 72
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft
-J n
0 1000 2000 3000 4000 5000 Time (s)
Figure 44 4-inch Break (3304 MWt)
Core Mixture Level 73
Westinghouse Non-Proprietary Class 3
-4 0~
E 0 1000 2000 3000 4000 5000 Time (s)
Figure 45 4-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.25 ft) 74
Westinghouse Non-Proprietary Class 3 15 00 - . . . . . . . . ...
.2 1000-5000 . . . . . . . .. . . . . .. . . . . . .. . . . . .. . . . . . . . .. . . . . . . .. . . . . . .. . . .
I I I I I II I I I I I 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 46 6-inch Break (3304 MWt)
RCS Pressure 75
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft (D
cI.
0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 47 6-inch Break (3304 MWt)
Core Mixture Level 76
Westinghouse Non-Proprietary Class 3 1500 . .....
U')
1000- .......
500-0 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 48 8.75-inch Break (3304 MWt)
RCS Pressure 77
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft
-4 X,
M.
0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 49 8.75-inch Break (3304 MWt)
Core Mixture Level 78
Westinghouse Non-Proprietary Class 3 0~
E 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 50 8.75-inch Break (3304 MWt)
Clad Temperature at PCT Elevation (11.50 ft) 79
Westinghouse Non-Proprietary Class 3 2 ) 15 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(D 1000.
5 0 I I I" 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 51 8.75-inch Break (3600 MWt)
RCS Pressure 80
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft
-4 X) 15 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 52 8.75-inch Break (3600 MWt)
Core Mixture Level 81
Westinghouse Non-Proprietary Class 3 0 8 0 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
600 - . .. .. . . .. . . .. . . ..
400-200 I I I 1 I, 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 53 8.75-inch Break (3600 MWt)
Core Exit Vapor Temperature 82
Westinghouse Non-Proprietary Class 3 Li ( Broken L2 (intact Loopp L3 (Intact Loop)
L4 Intact Loop) 1150 11001 . ......
1050 . .............
"* 1000 .........
950 . .....
C2 onn 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 54 8.75-inch Break (3600 MWt)
Broken and Intact Loops Secondary Pressures 83
Westinghouse Non-Proprietary Class 3 U.3 E
a, .
c~400-0 0 I I I I I I I II I I I I I I I I I I I I I I I III 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 55 8.75-inch Break (3600 MWt)
Break Vapor Flow Rate 84
Westinghouse Non-Proprietary Class 3 CI 1000-Uf) 500" 0-0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 56 8.75-inch Break (3600 MWt)
Break Liquid Flow Rate 85
Westinghouse Non-Proprietary Class 3 L1 Broken Loop)
L2 Intact Loop L3 Intact Loop L4 Intact Loop) 1000 800- ....................
E 600 - ............
-o 0
400- ...................... L.I~
. . . . . . . .. . . . . . .. . . . I L.M 200" ......................
U 0 5 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 57 8.75-inch Break (3600 MIWt)
Broken and Intact Loops Accumulator Flow Rates 86
Westinghouse Non-Proprietary Class 3 L1 Broken Loop Loop -
CHG Flow)
L1 Broken Loop) HHSI/RHR Flow)
L2 Intact L3 Intact Loop)
L4 Intact Loop)
AMfA-,
,tUU
-r -
I.
300-U, . .... . .
E I.
I.
-o I.
Q.)
200-0 U,
U, 100-
'1~
/'
1 1 fl-I U
r 1 I I I . I I I I . I I I I . i i 0 1000 2000 3000 4000 5000 6000 Time (s)
Figure 58 8.75-inch Break (3600 MWt)
Broken and Intact Loops Pumped Safety Injection Flow Rates 87
Westinghouse Non-Proprietary Class 3 1
1 1200-a,-
1000-1 E
'-- 800-600-400-200 I I I , I I I I I I I I , I I 2000 3000 4000 5000 6000 Time (s)
Figure 59 8.75-inch Break (3600 MWt)
Clad Temperature at PCT Elevation (12.0 ft) 88
Westinghouse Non-Proprietary Class 3 12UU 10 0 S 1U.
8000
. . . . . . . .. . .. . .. . . .. . .. . .. . .. .... I". . . .
E
.. /........................................
400.o .....
200 I I , I I I , I I I I 2000 3000 4000 5000 6000 Time (s)
Figure 60 8.75-inch Break (3600 MWt)
Hot Spot Fluid Temperature at PCT Elevation (12.0 ft) 89
Westinghouse Non-Proprietary Class 3 5
10 4
10 . ... . . . .. . ..
ITa.
CN M-,
a)..
2 C)l 10 UD C
- "102I 200 2803024050 2000 2800 3600 4400 5200 6000 Time (s)
Figure 61 8.75-inch Break (3600 MWt)
Rod Film Heat Transfer Coefficient at PCT Elevation (12.0 ft) 90
Westinghouse Non-Proprietary Class 3 oCl)
- 18 0 0 . . . . . . . . . . . . . . . . . . . . . . . . .
cD 1600-1200-1000 I*
0 1000 2000 3000 4000 5000 Time (s)
Figure 62 1.5-inch Break (3600 MWt)
RCS Pressure 91
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft XJ 0 1000 2000 Time (s)3000 4000 5000 Figure 63 1.5-inch Break (3600 MWt)
Core Mixture Level 92
Westinghouse Non-Proprietary Class 3 I ouu CL) 1 0 . . . ... . . . . .
S 1600 . . . . . . . . . . . . . . . .
=3 1200 1 0 0. . . . . . . .... .. . . . . . . . . . . . . . ..
1200 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 64 2-inch Break (3600 MWt)
RCS Pressure 93
Westinghouse Non-Proprietary Class 3 Core Mixture Level
- - --- Top of Core = 22.0778 ft
. 30" X)
MJ 0 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 65 2-inch Break (3600 MWt)
Core Mixture Level 94
Westinghouse Non-Proprietary Class 3 I..
CL E
la, 1000 2000 3000 4000 5000 6000 7000 Time (s)
Figure 66 2-inchlBreak (3600 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 95
Westinghouse Non-Proprietary Class 3 CD
--3 c_ 1000-500 -. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .
N I I I I , I I I I , I I I , I I I I , I I I I 0 1000 2000 3000 4000 5000 Time (s)
Figure 67 3-inch Break (3600 MWt)
RCS Pressure 96
Westinghouse Non-Proprietary Class 3 Core Mixture Level ,
- - --- Top of Core = 22.0778 ft
-4
->< 25-0 1000 2000 3000 4000 5000 Time (s)
Figure 68 3-inch Break (3600 MWt)
Core Mixture Level 97
Westinghouse Non-Proprietary Class 3
=3 0
a) 80 0. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .. . . . . . . . . . .
600 400 I I I I, I I I , I I I I I I I I , I I I I 0 1000 2000 3000 4000 5000 Time (s)
Figure,69 3-inch Break (3600 MWt)
Clad Temperature at PCT Elevation (11.25 ft) 98
Westinghouse Non-Proprietary Class 3
.2 1500 ... . . . . . . . . . . . . . . . . . . . . ... . . .
=3 0-0 1000 2000 3000 4000 5000 Time (s)
Figure 70 4-inch Break (3600 MWt)
RCS Pressure 99
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft X,
MJ 0 1000 2000lime (s)3000 4000 5000 Figure 71 4-inch Break (3600 MWt)
Core Mixture Level 100
Westinghouse Non-Proprietary Class 3 I° .
E
¢) 800.. . .
600 . . . . . .. . . . . . . . . ."
600 40 I i I i , I i i i , i i I i*
0 1000 2000 3000 4000 5000 Time (s)
Figure 72 4-inch Break (3600 MWt)
Clad Temperature at PCT Elevation (11.25 ft) 101
Westinghouse Non-Proprietary Class 3 2000-
.2 15 00 ... . . . . . . . . . . . . . . . . .. . .................... ..
C',
C,,
_ 1000 .
0-0 1000 2000 3000 4000 5000 Time (s)
Figure 73 6-inch Break (3600 MWt)
RCS Pressure 102
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top, of Core = 22.0778 ft X.
0 1000 2000 3000 4000 5000 Time (s)
Figure 74.
6-inch Break (3600 MWt)
Core Mixture Level 103
Westinghouse Non-Proprietary Class 3 CL) c-0 1000 2000 3000 4000 5000 Time (s)
Figure 75 8.5-inch Break (3600 MWt)
RCS Pressure 104
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft
-4 X
1000 2000 Time 0
(s)3000 4000 5000 Figure 76 8.5-inch Breakc (3600 MWt)
Core Mixture Level 1 105
Westinghouse Non-Proprietary Class 3
. 1500 -
CL C0 CD r 1000-500 i I I -
0 1000 2000 3000 4000 5000 Time (s)
Figure 77 9-inch Break (3600 MWt)
RCS Pressure 106
Westinghouse Non-Proprietary Class 3 Core Mixture Level Top of Core = 22.0778 ft 75 XJ 0 1000 2000 3000 4000 5000 Time (s)
Figure 78 9-inch Break (3600 MWt)
Core Mixture Level 1107
Westinghouse Non-Proprietary Class 3 U,-
800 -
E 600 -
400 200- I 1. I I I , ,
1000 2000 3000 4000 5000 Time (s)
Figure 79 9-inch Break (3600 MWt)
Clad Temperature at PCT Elevation (11.75 ft) 108