Computer Programs

NAME OR DESIGNATION OF PROGRAM, COMPUTER, DESCRIPTION OF PROBLEM OR FUNCTION, METHOD OF SOLUTION, RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM, TYPICAL RUNNING TIME, UNUSUAL FEATURES OF THE PROGRAM, RELATED AND AUXILIARY PROGRAMS, STATUS, REFERENCES, MACHINE REQUIREMENTS, LANGUAGE, OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED, OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS, NAME AND ESTABLISHMENT OF AUTHOR, MATERIAL, CATEGORIES

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Program name | Package id | Status | Status date |
---|---|---|---|

RELAP5/MOD1/018 | NESC0917/15 | Tested | 29-JUL-1985 |

RELAP5/MOD1/029 | NESC0917/17 | Tested | 29-JUL-1985 |

RELAP5/MOD1/025 | NESC0917/18 | Tested | 04-JUL-1985 |

RELAP5/MOD1/029 | NESC0917/20 | Tested | 05-MAR-1991 |

Machines used:

Package ID | Orig. computer | Test computer |
---|---|---|

NESC0917/15 | FACOM VP-100 | IBM 3084Q |

NESC0917/17 | CDC CYBER 176 | CDC CYBER 740 |

NESC0917/18 | IBM 370 series | IBM 3081 |

NESC0917/20 | DEC VAX series | DEC VAX 8810 |

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3. DESCRIPTION OF PROBLEM OR FUNCTION

RELAP5 was developed to describe the behavior of a light water reactor (LWR) subjected to postulated transients such as loss of coolant from large or small pipe breaks, pump failures, etc. RELAP5 calculates fluid conditions such as velocities, pressures, densities, qualities, temperatures; thermal conditions such as surface temperatures, temperature distributions, heat fluxes; pump conditions; trip conditions; reactor power and reactivity from point reactor kinetics; and control system variables. In addition to reactor applications, the program can be applied to transient analysis of other thermal- hydraulic systems with water as the fluid.

RELAP5/MOD1 uses a five equation two-phase flow hydrodynamic model consisting of the two phasic continuity equations, the two phasic momentum equations, and an overall energy equation augmented by the requirement that one of the phases is assumed saturated. In this model only two interphase constitutive relations are required, those for interphase drag and interphase mass exchange. Models are included for abrupt area changes, choking, mass transfer, interphase drag, wall friction, and branching.

RELAP5 was developed to describe the behavior of a light water reactor (LWR) subjected to postulated transients such as loss of coolant from large or small pipe breaks, pump failures, etc. RELAP5 calculates fluid conditions such as velocities, pressures, densities, qualities, temperatures; thermal conditions such as surface temperatures, temperature distributions, heat fluxes; pump conditions; trip conditions; reactor power and reactivity from point reactor kinetics; and control system variables. In addition to reactor applications, the program can be applied to transient analysis of other thermal- hydraulic systems with water as the fluid.

RELAP5/MOD1 uses a five equation two-phase flow hydrodynamic model consisting of the two phasic continuity equations, the two phasic momentum equations, and an overall energy equation augmented by the requirement that one of the phases is assumed saturated. In this model only two interphase constitutive relations are required, those for interphase drag and interphase mass exchange. Models are included for abrupt area changes, choking, mass transfer, interphase drag, wall friction, and branching.

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4. METHOD OF SOLUTION

For hydrodynamics, the space approximation uses a staggered mesh, where integral forms of the continuity and energy equations are approximated over control volumes, and line integral forms of the momentum equations are applied from the midpoint of one control volume to the midpoint of the adjoining control volume. Hydrodynamic equations are advanced in time using a semi-implicit, linearized method. Heat conduction is approximated by finite differences and advanced by the Crank-Nicolson scheme. A modified Runge-Kutta technique for stiff equations is used to solve the reactor kinetics equations. The interaction among hydrodynamics, heat conduction, trips, reactor kinetics, and the control system is explicit.

For hydrodynamics, the space approximation uses a staggered mesh, where integral forms of the continuity and energy equations are approximated over control volumes, and line integral forms of the momentum equations are applied from the midpoint of one control volume to the midpoint of the adjoining control volume. Hydrodynamic equations are advanced in time using a semi-implicit, linearized method. Heat conduction is approximated by finite differences and advanced by the Crank-Nicolson scheme. A modified Runge-Kutta technique for stiff equations is used to solve the reactor kinetics equations. The interaction among hydrodynamics, heat conduction, trips, reactor kinetics, and the control system is explicit.

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5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The limitations on the number of hydrodynamic volumes, heat structures, trips, minor edits, etc. are primarily dictated by the available memory of the computer. Dynamic allocation of storage is used for all problem- dependent data. Design of the fields used for input data can also impose limits. Problems with over 150 hydrodynamic volumes and over 100 heat structures have been run on a CYBER176 using 270K of SCM and 200K of LCM storage for input processing and less during transient analysis.

The limitations on the number of hydrodynamic volumes, heat structures, trips, minor edits, etc. are primarily dictated by the available memory of the computer. Dynamic allocation of storage is used for all problem- dependent data. Design of the fields used for input data can also impose limits. Problems with over 150 hydrodynamic volumes and over 100 heat structures have been run on a CYBER176 using 270K of SCM and 200K of LCM storage for input processing and less during transient analysis.

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6. TYPICAL RUNNING TIME

The computer time depends on the number of volumes, heat structures, and the type of transient. Simulation of a postulated small break loss-of-coolant accident for the LOFT reactor using 87 volumes, 96 junctions, and 32 heat structures required 3152 seconds of CYBER176 time for 3600 seconds of reactor transient analysis. EDHTRK sample problem execution time is approximately 20 CP seconds on a CDC CYBER176 and 39 CP seconds on a CDC CYBER175; WORKSHOP PROBLEM 2 40 CP seconds on a CDC CYBER176 and 71 CP seconds on a CDC CYBER175; WORKSHOP PROBLEM 3 118 CP seconds on a CDC CYBER176 and 215 CP seconds on a CDC CYBER175. Execution of the sample problems on the IBM3033 and IBM370/195 requires from 1 second to 3 minutes of CPU time.

The computer time depends on the number of volumes, heat structures, and the type of transient. Simulation of a postulated small break loss-of-coolant accident for the LOFT reactor using 87 volumes, 96 junctions, and 32 heat structures required 3152 seconds of CYBER176 time for 3600 seconds of reactor transient analysis. EDHTRK sample problem execution time is approximately 20 CP seconds on a CDC CYBER176 and 39 CP seconds on a CDC CYBER175; WORKSHOP PROBLEM 2 40 CP seconds on a CDC CYBER176 and 71 CP seconds on a CDC CYBER175; WORKSHOP PROBLEM 3 118 CP seconds on a CDC CYBER176 and 215 CP seconds on a CDC CYBER175. Execution of the sample problems on the IBM3033 and IBM370/195 requires from 1 second to 3 minutes of CPU time.

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8. RELATED AND AUXILIARY PROGRAMS

The primary improvement in RELAP5 compared to the earlier RELAP4 series (NESC No. 369) is the use of an advanced hydrodynamic model for two-phase flow which allows different velocities and different temperatures for the phases. RELAP5/MOD1 extends the earlier RELAP5/MOD0 capability to include models unique to small break situations, and provides added capability for modeling accumulators, noncondensible gas, nucleonics, control systems, separators, and boron concentrations. MOD1 also contains improvements in the flow regime maps, choked flow models, general running time, and output edits.

The primary improvement in RELAP5 compared to the earlier RELAP4 series (NESC No. 369) is the use of an advanced hydrodynamic model for two-phase flow which allows different velocities and different temperatures for the phases. RELAP5/MOD1 extends the earlier RELAP5/MOD0 capability to include models unique to small break situations, and provides added capability for modeling accumulators, noncondensible gas, nucleonics, control systems, separators, and boron concentrations. MOD1 also contains improvements in the flow regime maps, choked flow models, general running time, and output edits.

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Package ID | Status date | Status |
---|---|---|

NESC0917/15 | 29-JUL-1985 | tested vectorized |

NESC0917/17 | 29-JUL-1985 | Tested at NEADB |

NESC0917/18 | 04-JUL-1985 | Tested at NEADB |

NESC0917/20 | 05-MAR-1991 | Tested at NEADB |

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10. REFERENCES

- RELAP5/MOD1/008, NESC No. 917.3033, RELAP5/MOD1/008 Tape

and Implementation Information,

National Energy Software Center Note 84-11, February 17, 1984.

- P. Saha, J.H. Jo, L. Neymotin, U.S. Rohatgi, and G. Slovik,

Independent Assessment of TRAC-PD2 and RELAP5/MOD1 Codes at BNL in FY 1981,

NUREG/CR-3148, (BNL-NUREG-51645), December 1982.

- J.M. McGlaun and L.N. Kmetyk,

RELAP5 Assessments: Semiscale Natural Circulation Tests S-NC-2 and S-NC-7,

NUREG/CR-3258 (SAND83-0833), May 1983.

- R.A. Riemke, h.Chow, and V.H. Ranson,

RELAP5/MOD1 Code Manual Volume 3: Checkout Problems summary,

EGG-NSMD-6182, February 1983.

- D.G. Hall and E.C. Johnson,

RELAP5/mod1 Quick Reference Manual,

EGG-CDD-6027, October 1982.

- RELAP5/MOD1/008, NESC No. 917.3033, RELAP5/MOD1/008 Tape

and Implementation Information,

National Energy Software Center Note 84-11, February 17, 1984.

- P. Saha, J.H. Jo, L. Neymotin, U.S. Rohatgi, and G. Slovik,

Independent Assessment of TRAC-PD2 and RELAP5/MOD1 Codes at BNL in FY 1981,

NUREG/CR-3148, (BNL-NUREG-51645), December 1982.

- J.M. McGlaun and L.N. Kmetyk,

RELAP5 Assessments: Semiscale Natural Circulation Tests S-NC-2 and S-NC-7,

NUREG/CR-3258 (SAND83-0833), May 1983.

- R.A. Riemke, h.Chow, and V.H. Ranson,

RELAP5/MOD1 Code Manual Volume 3: Checkout Problems summary,

EGG-NSMD-6182, February 1983.

- D.G. Hall and E.C. Johnson,

RELAP5/mod1 Quick Reference Manual,

EGG-CDD-6027, October 1982.

NESC0917/15, included references:

- Misako ISHIGURO, Hiroo HARADA, Naohisa SHINOZAWA, andKen-itsu NARAOKA:

"Vectorization of LWR Transient Analysis Code RELAP5/MOD1 and Its

Effects"

JAERI-M 85-040 (February 1985)

NESC0917/17, included references:

- M. Birgersson:Description of RELAP5/MOD1/029 CDC UPDATE Format Tape and

Implementation Information.

NESC Note 85-36 (December 24, 1984)

- M. Birgersson:

Description of RELAP5/MOD1/029 Edition B Tape for Reading on

Non-CDC Systems and Implementation Information.

NESC Note 85-37 (December 24, 1984)

- Environmental Library Installation Procedures.

How to Use (September 1983)

- D.G. Hall and E.C. Johnson:

RELAP5/MOD1 Quick Reference Manual.

EGG-CDD-6027 (October 1982)

- M. Birgersson:

Additional Material for Use with the CDC Cyber 176 Version

of RELAP5/MOD1/029

NESC Note 88-55 (March 15,1988)

NESC0917/18, included references:

- W. Kolar and W. Brewka:The IBM-Version of RELAP5/MOD1.

EUR 6977 EN (1983)

- M. Birgersson:

Steam Tables Conversion Program Source Listing. (June 1986)

- V.H. RANSOM, R.J. WAGNER, J.A. TRAPP and.....

RELAP5/MOD1 Code Manual, Vol 1: System models and Numerical Methods

NUREG/CR-1826, Rev 4, March 1982

- R.J. WAGNER, V.H. RANSOM, R.J. WAGNER, J.A. TRAPP and.....

RELAP5/MOD1 Code Manual, Vol 2: Users Guide and Input Requirements

NUREG/CR-1826, March 1982

R.A. RIEMKE, H. CHOW, V.H. RANSOM

RELAP5/MOD1 Code Manual, Vol 3: Checkout Problems Summary

EGG-NSMD-6182, Feb 1983

- RELAP5 Project Staff

RELAP5 NEWSLETTER

EGG-SAAM-6428, October 1983

- NRTS Environmental Subroutine Manual

DE-AC07-76IDO1570

- W. KOLAR

The Implementation of RELAP5/MOD1/019 on an AMDAHL 470/V8

(Nov 1983)

NESC0917/20, included references:

- B. Mavko, M. Gregoric and I. Parzer:Conversion of RELAP5/MOD1/025 VAX Version to RELAP5/MOD1/029 VAX

Version

IJS-DP-5355 (December 1988).

- Graphs of RELAP Output (February 1991).

- D.G. Hall and E.C. Johnson:

RELAP5/MOD1 Quick Reference Manual

EGG-CDD-6027 (October 1982)

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11. MACHINE REQUIREMENTS

RELAP5 has run on a 64K CDC7600 and a 132K CYBER176 both with and without use of LCM storage, and a 256K CDC CYBER176 without use of ECS storage. The CDC RELAP5 package contains options (implementated through the CDC UPDATE utility program) intended to allow RELAP5 implementation on a CYBER76 operating under SCOPE2, and CYBER175 under NOS or NOS2, and a CYBER170 or similar CYBER series hardware under NOS/BE.

RELAP5 on an IBM3033 or IBM 370/195 requires from 980K or 1500K bytes.

RELAP5 has run on a 64K CDC7600 and a 132K CYBER176 both with and without use of LCM storage, and a 256K CDC CYBER176 without use of ECS storage. The CDC RELAP5 package contains options (implementated through the CDC UPDATE utility program) intended to allow RELAP5 implementation on a CYBER76 operating under SCOPE2, and CYBER175 under NOS or NOS2, and a CYBER170 or similar CYBER series hardware under NOS/BE.

RELAP5 on an IBM3033 or IBM 370/195 requires from 980K or 1500K bytes.

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Package ID | Computer language |
---|---|

NESC0917/15 | FORTRAN+ASSEMBLER |

NESC0917/17 | FORTRAN+COMPASS |

NESC0917/18 | FORTRAN-77 |

NESC0917/20 | FORTRAN+ASSEMBLER |

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14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

RELAP5

contains a limited plotting capability. It has been interfaced to the local INEL system and proprietary graphics software to plot and compare simulation results with experiment. A number of the NRTS Environmental Subroutines are written in the CDC assembly language COMPASS, including those for input and output processing, and packing and unpacking. RELAP5 is written exclusively in FORTRAN but uses MASK, SHIFT and Boolean AND and OR operations to pack and unpack integer data. Several of the routines which are CDC operating system or INEL computing environment dependent will require modification or replacement in other environments. The RELAP5 Edition B package is the same as the C176 edition except that it is written in a format that can be read on non-CDC machines.

The IBM version of RELAP5 contains an assembly language subroutine JTIME which only runs on VM systems. Users with other operating systems must replace this routine, which requests the remaining CPU time of a job, with an alternative routine suited to their computing environment.

RELAP5

contains a limited plotting capability. It has been interfaced to the local INEL system and proprietary graphics software to plot and compare simulation results with experiment. A number of the NRTS Environmental Subroutines are written in the CDC assembly language COMPASS, including those for input and output processing, and packing and unpacking. RELAP5 is written exclusively in FORTRAN but uses MASK, SHIFT and Boolean AND and OR operations to pack and unpack integer data. Several of the routines which are CDC operating system or INEL computing environment dependent will require modification or replacement in other environments. The RELAP5 Edition B package is the same as the C176 edition except that it is written in a format that can be read on non-CDC machines.

The IBM version of RELAP5 contains an assembly language subroutine JTIME which only runs on VM systems. Users with other operating systems must replace this routine, which requests the remaining CPU time of a job, with an alternative routine suited to their computing environment.

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15. NAME AND ESTABLISHMENT OF AUTHOR

C176 & C176B V.H. Ransom, R.J. Wagner, K.E. Carlson,

J.A. Trapp, D.M. Kiser, H.H. Kuo,

H.M. Chow, R.A. Nelson, D.G. Hall,

S.W. James, and E.C. Johnson

EG&G Idaho, Inc.

P.O. Box 1625

Idaho Falls, Idaho 83415

3033 L. Garcia de Viedma*

N.E.A. Data Bank

91191 Gif-sur-Yvette

France

* Contact

C176 & C176B V.H. Ransom, R.J. Wagner, K.E. Carlson,

J.A. Trapp, D.M. Kiser, H.H. Kuo,

H.M. Chow, R.A. Nelson, D.G. Hall,

S.W. James, and E.C. Johnson

EG&G Idaho, Inc.

P.O. Box 1625

Idaho Falls, Idaho 83415

3033 L. Garcia de Viedma*

N.E.A. Data Bank

91191 Gif-sur-Yvette

France

* Contact

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NESC0917/15

File name | File description | Records |
---|---|---|

NESC0917_15.003 | INFORMATION FILE | 92 |

NESC0917_15.004 | ENVIRONMENTAL ROUTINES (ASSEMBLER) | 717 |

NESC0917_15.005 | RELAP5/MOD1/018 ORIGINAL SOURCE (FORTRAN) | 79659 |

NESC0917_15.006 | RELAP5/MOD1/018 VECTORIZED SOURCE (FORTRAN) | 25915 |

NESC0917_15.007 | OVERLAY CARDS | 204 |

NESC0917_15.008 | TEST CASE INPUT DATA | 1920 |

NESC0917_15.009 | JCL FOR RUN ON FACOM VP-100 | 41 |

NESC0917_15.011 | RELAP5/MOD1/018 VECTORIZED SOURCE MODIFIED | 25958 |

NESC0917_15.012 | MACRO ROUTINES (ASSEMBLER) | 50 |

NESC0917_15.013 | JCL FOR RUN ON IBM3084Q | 42 |

NESC0917_15.014 | STEAM TABLES (BINARY) | 7 |

NESC0917/17

File name | File description | Records |
---|---|---|

NESC0917_17.003 | INFORMATION FILE | 375 |

NESC0917_17.004 | RELAP5/MOD1/029 SOURCE PROGRAM (FORTRAN) | 40717 |

NESC0917_17.005 | ENVIRONMENTAL ROUTINES SOURCE (FORTRAN) | 36983 |

NESC0917_17.006 | ORIGINAL INPUT DATA COLLECTION | 22781 |

NESC0917_17.007 | CYBER CONTROL PROCEDURES | 444 |

NESC0917_17.008 | UPDATE INPUT TO GENERATE CYCLES 19 THRU 29 | 1788 |

NESC0917_17.009 | EDHTRK INPUT DATA | 159 |

NESC0917_17.010 | EDHTRK EG&G TEST RUN PRINTED OUTPUT | 5576 |

NESC0917_17.011 | PROB2 TEST INPUT DATA | 1002 |

NESC0917_17.012 | PROB2 EG&G TEST RUN PRINTED OUTPUT | 8584 |

NESC0917_17.013 | PROB3 INPUT DATA | 230 |

NESC0917_17.014 | PROB3 EG&G TEST RUN PRINTED OUTPUT | 3407 |

NESC0917_17.015 | JCL SUPPLIED BY NESC | 1 |

NESC0917_17.016 | JCL USED AT NEADB FOR IMPLEMENTATION | 218 |

NESC0917_17.017 | RELAP5 TEST RUN SYSTEM OUTPUT | 11430 |

NESC0917_17.018 | EDHTRK NEADB TEST RUN PRINTED OUTPUT | 5191 |

NESC0917_17.019 | PROB2 NEADB TEST RUN PRINTED OUTPUT | 8066 |

NESC0917_17.020 | PROB3 NEADB TEST RUN PRINTED OUTPUT | 3098 |

NESC0917/18

File name | File description | Records |
---|---|---|

NESC0917_18.003 | INFORMATION FILE | 431 |

NESC0917_18.004 | ENVIRONMENTAL ROUTINES SOURCE (ASSEMBLER) | 398 |

NESC0917_18.005 | ENVIRONMENTAL ROUTINES SOURCE (FORTRAN) | 5903 |

NESC0917_18.006 | RELAP5/MOD1/025 SOURCE (FORTRAN) | 54668 |

NESC0917_18.007 | RELAP5 INPUT DATA COLLECTION (ORIGINAL) | 22746 |

NESC0917_18.008 | JCL TO LOAD RELAP5 AND TEST CASE 1 EXEC. | 34 |

NESC0917_18.009 | RELAP5 TEST CASE 1 INPUT DATA | 152 |

NESC0917_18.010 | RELAP5 TEST CASE 2 INPUT DATA | 992 |

NESC0917_18.011 | RELAP5 TEST CASE 3 INPUT DATA | 222 |

NESC0917_18.012 | RELAP5 TEST CASE 1 PRINTED OUTPUT | 17387 |

NESC0917_18.013 | RELAP5 TEST CASE 2 PRINTED OUTPUT | 8656 |

NESC0917_18.014 | RELAP5 TEST CASE 3 PRINTED OUTPUT | 3514 |

NESC0917_18.015 | STEAM TABLES (BINARY) | 7 |

NESC0917/20

File name | File description | Records |
---|---|---|

NESC0917_20.001 | Information file | 125 |

NESC0917_20.002 | Command file to compile the R5RTL version | 9 |

NESC0917_20.003 | Command file to compile the RELAP version | 9 |

NESC0917_20.004 | Command file to link the R5RTL version | 1 |

NESC0917_20.005 | Command file to link the RELAP version | 1 |

NESC0917_20.006 | Command file for file assignement | 67 |

NESC0917_20.007 | Command file to run Relap5/MOD1/029 | 249 |

NESC0917_20.008 | R5RTL Relap version source file | 50065 |

NESC0917_20.009 | RELAP Relap version source file | 50798 |

NESC0917_20.010 | STEAM source file | 24 |

NESC0917_20.011 | ENV subroutine | 5219 |

NESC0917_20.012 | ENV2 subroutine | 439 |

NESC0917_20.013 | ENV2A subroutine | 6 |

NESC0917_20.014 | UNUSED subroutine | 1766 |

NESC0917_20.015 | Changes in the RELAP source routines | 162 |

NESC0917_20.016 | Changes in the RELAP source routines | 256 |

NESC0917_20.017 | Changes in the RELAP source routines | 274 |

NESC0917_20.018 | Changes in the R5RTL source routines | 743 |

NESC0917_20.019 | UNUSED macro file in assembler | 157 |

NESC0917_20.020 | AND macro routine in Assembler | 24 |

NESC0917_20.021 | NOT macro routine in assembler | 15 |

NESC0917_20.022 | OR macro routine in assembler | 17 |

NESC0917_20.023 | SHIFT macro routine in assembler | 105 |

NESC0917_20.024 | SHIFTI macro routine in assembler | 105 |

NESC0917_20.025 | XOR macro routine in assembler | 36 |

NESC0917_20.026 | Binary steam table G_floating precision | 54 |

NESC0917_20.027 | Binary steam table no G_floating precision | 54 |

NESC0917_20.028 | Decimal steam table | 4457 |

NESC0917_20.029 | Sample1 input file | 152 |

NESC0917_20.030 | Sample2 input file | 992 |

NESC0917_20.031 | Sample3 input file | 222 |

NESC0917_20.032 | Sample1 brief output file from RELAP version | 152 |

NESC0917_20.033 | Sample2 brief output file from RELAP version | 280 |

NESC0917_20.034 | Sample3 brief output file from RELAP version | 358 |

NESC0917_20.035 | Sample1 brief output file from R5RTL version | 152 |

NESC0917_20.036 | Sample2 brief output file from R5RTL version | 280 |

NESC0917_20.037 | Sample3 brief output file from R5RTL version | 358 |

NESC0917_20.038 | Sample1 output file from RELAP version | 5401 |

NESC0917_20.039 | Sample2 output file from RELAP version | 8299 |

NESC0917_20.040 | Sample3 output file from RELAP version | 3157 |

NESC0917_20.041 | Sample1 output file from R5RTL version | 5401 |

NESC0917_20.042 | Sample2 output file from R5RTL version | 8299 |

NESC0917_20.043 | Sample3 output file from R5RTL version | 3158 |

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- G. Radiological Safety, Hazard and Accident Analysis
- H. Heat Transfer and Fluid Flow

Keywords: LWR reactors, accidents, blowdown, control systems, heat transfer, hydrodynamics, loss-of-coolant accident, reactor kinetics, reactor safety, simulation, thermal conduction, transients, two-phase flow.