NESC0369 RELAP-4.

1. NAME OR DESIGNATION OF PROGRAM:  RELAP-4.

3. DESCRIPTION OF PROBLEM OR FUNCTION

RELAP4 has been developed to describe the behavior of water-cooled nuclear reactors subjected to  postulated transients, such as those resulting from loss-of-coolant, pump failure, or power excursions. The program calculates fluid conditions such as flow, pressure, mass inventory, and quality; thermal conditions such as surface temperatures, temperature profiles, and energy distributions; and heat fluxes in power generating and dissipating elements. The program also calculates reactor power, decay heat, and reactivity. In addition to describing transients in boiling-water and pressurized-water reactors, the program is sufficiently versatile to describe transients in experimental thermal-hydraulic systems.

RELAP4/MOD6 was developed specifically to add a capability to the earlier RELAP codes for calculating PWR reflood phenomena.

REALP-4/6-KFK is a modification of RELAP4/MOD6 update 4 which generates a file for transferring boundary conditions to the fuel rod code SSYST-2 (NEA 0684).

RELAP4/MOD7/101: Performs best estimate analyses of nuclear reactors or related systems undergoing a transient. Transient thermal- hydraulic, two-phase phenomena are calculated from formulations of one-dimensional, homogeneous, equilibrium conservation equations for water mass, momentum, and energy. Heat structures are modeled using  a transient one-dimensional heat conduction solution that is coupled to the fluid through heat transfer relations. Various explicit models are used to calculate nonhomogeneous, nonequilibrium behavior including a phase separation model, a vertical slip model, and a nonequilibrium model. Other models are used to represent critical flow, reactor kinetics, pressurized water reactor reflood behavior,  nuclear fuel rod swelling and blockage, and components such as pumps, valves, and accumulators.

4. METHOD OF SOLUTION

The RELAP4 user must define the geometric features of the system to be analyzed as well as an appropriate set  of initial conditions. RELAP4 then solves an integral form of the fluid conservation and state equations applied to each user-defined  control volume.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

Maxima of -
     9 minor edit variables
    20 time-step cards
    20 trip control cards
   100 junctions (flow paths) between volumes
     5 bubble-parameter sets
     5 time-dependent volume descriptions on cards
    12 pumps
    75 control volumes
    10 check valve types
     5 normalized leak-area-versus-time curves
    20 fill system curves
    50 heat slabs
    20 heat slab geometries
     7 heat slab materials
    50 core sections
    99 data sets for heat exchangers without conduction

6. TYPICAL RUNNING TIME

For a PWR modeled with 30 to 40 fluid volumes, running time through refill may range from 15 to 60 minutes or more on the CDC7600 and from 2 to 8 hours or more on the IBM360/75.
RELAP-4/6-KFK (NESC0369/19): NEA-DB executed the test case on IBM 3033 IN 43 CP seconds.
RELAP4/MOD7/101: For a PWR modeled with 30 to 40 fluid volumes, running time through reflood may range from 30 to 90 minutes or more on the CDC 7600. The four sample problems require a total of 55 CP seconds to run on a CDC 7600.

7. UNUSUAL FEATURES OF THE PROGRAM

RELAP4 provides the following features: a fully-implicit integration technique, steam tables that  contain derivatives, heat conduction between fluid volumes, momentum flux terms in the hydraulic equations, a pump model with inertia and friction, a limited air flow capability, a separate hot channel calculation, and core cross flow.
   RELAP4/MOD6 contains  the following  four program  operations -
standard RELAP4 (minimum controls), RELAP4-EM (a part of the NRC evaluation model), RELAP4-FLOOD (reflooding rates), and RELAP4- CONTAINMENT (special containment models).
RELAP4/MOD7/101 contains the following four program operations - standard RELAP4 (minimum controls), RELAP4-EM (a part of the NRC evaluation model), RELAP4-REFLOOD (reflooding rates), and RELAP4- CONTAINMENT (special containment models).

8. RELATED AND AUXILIARY PROGRAMS

RELAP4/MOD6 uses PLOTR4M to produce both CalComp and microfilm plots of appropriate variables versus time from data stored on a RELAP4 output data tape. STH20G is used to generate tables of water properties in the proper RELAP4 format for the IBM360 version. PRELOAD reduces the amount of storage required to run RELAP4.

10. REFERENCES

- RELAP4/MOD5, A Computer Program for Transient Thermal-hydraulic
  Analysis of Nuclear Reactors and Related Systems
  User's Manual, Volume  I: RELAP4/MOD5 Description, Volume II:
  Program Implementation,  Volume  III: Checkout  Applications
  ANCR-NUREG-1335 (September 1976).
- RELAP4/MOD6, A Computer Program for Transient Thermal-hydraulic
  Analysis of Nuclear Reactors and Related Systems User's Manual
  CDAP TR 003 (January 1978) with Errata (August 1978).
- Demonstration Problems for RELAP4/MOD6, Update 3
  CDAP-TR-008 (April 1978).
- RELAP4/MOD6 Update 4, NESC No. 369.7600D, Tape Contents
  Description and Implementation Instructions
  NESC Note 79-13 (September 5, 197)8.
- RELAP4/MOD6 Update 4, NESC No. 369.7600E, Tape Contents
  Description
  NESC Note 79-14 (September 5, 1978).
- RELAP4/MOD6 Update 4, NESC No. 369.360F,Tape Contents Description
  and Implementation Instructions
  NESC Note 79-12 (September 5, 1978).
- W.H. Rettig:
  UPD - A Program to Update Source Decks, P01752; Addendum 1 to UPD
by R.C. Young and N.H. Marshall; Addendum 2 to UPD by G.L. Singer;    and Addendum 3 to UPD by W.H. Rettig.
- G.D. Brown, C.H. Bush, and R.A. Berman:
  The Integrated Graphics System for the SC4060: I. User's Manual,
  RM-5660-PR (December 1968).

11. MACHINE REQUIREMENTS

850K bytes (IBM360), 160,000 (octal) words of SCM and 200,000 (octal) words of LCM (CDC7600), 3 tape drives, and a CALCOMP plotter.
RELAP-4/6-KFK (NESC0369/19): To execute the test case on IBM 3033, 972 Kbytes of main storage are required.
RELAP4/MOD7/101 (NESC0369/20): Execution of the test cases on CDC 7600 requires 160,000 octal words of SCM adn 147,000 octal words of  LCM.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED

      OS/360,370
(IBM360,370), SCOPE (CDC7600).
RELAP-4/6-KFK (NESC0369/19): The test case was executed by NEA-DB using OS370/MVS-SE.
RELAP4/MOD7/101 (NESC0369/20): The test cases were executed on CDC 7600 under SCOPE2.1 LEVEL 545 with LCM.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

PLOTR4M as executed at NRTS makes use of the SC-4060 integrated graphics system for microfilm output in addition to the CalComp graphical output. The IGS subroutines SUBJEG, TITLEG, MODESG, SETUPG, GRIDG, LABELG, LINESG, POINTG, ERRZZ, SETSMG, PAGEG, and EXITG are included in the environmental subroutines file for the IBM360 version only.
The IBM360 transmittal tape contains 2314 and 3330 load modules of a special FORTRAN (H) compiler equivalent to the standard (H) compiler except that it uses a large table area allowing compilation of all RELAP4 source routines, including the large MIXFLO subroutine. A compilation region of 400K is sufficient for RELAP4; the OPT=2 option should be invoked.
The CDC7600 version is available in two editions: 7600D for reading on 7600 systems, 7600E for reading on 6600 systems. Both these editions are intended for use on CDC equipment only.
RELAP-4/MOD7/101 (NESC0369/20): The Edition B package is provided for those wishing to obtain this CDC CYBER 176 program for implementation on other than CDC systems.

15. NAME AND ESTABLISHMENT OF AUTHORS

                 P. North, G. L. Singer*, and J. E. Tolli+
                 EG&G Idaho, Inc.
                 P. O. Box 1625
                 Idaho Falls, Idaho  83401
* 7600 contact
+ 360 contact

For RELAP-4/6-KFK:
                 H. Borgwaldt (contact)
                 Kernforschungszentrum
                 Karlsruhe, F.R. Germany

RELAP4/MOD7/101: S.R. Behling, C.H. Burgess, H. Chow, K.G. Condie,
                 T.L. DeYoung, S.R. Fischer, C.E. Hendrix, M. Hsu,
                 G.A. Jayne, G.W. Johnson, D.M. Kiser,
                 S.D. Kucharski, G.E. McCreery, C.M. Mohr,
                 R.A. Nelson, R.J. Sand, G.L. Singer, D.L. Slegel,
                 H. Stadtke, J.E. Tolli, and L.R. Fitch*
                 EG&G Idaho, Inc.
                 P. O. Box 1625
                 Idaho Fallls, Idaho 83415, U.S.A.
* Contact

File name	File description	Records
NESC0369_11.001	INFORMATION FILE	109
NESC0369_11.002	RELAP4/M5 SOURCE PROGRAM (UNCOMPILABLE) EBCD	45570
NESC0369_11.003	CONVERT SOURCE PROGRAM (F4) EBCD	24
NESC0369_11.004	CONVERT JCL EBCD	12
NESC0369_11.005	CONVERT OUTPUT (COMPILABLE SOURCE,F4)EBCD	45570
NESC0369_11.006	ENVIRONMENTAL ROUTINES (F4 + ASSEMBLER) EBCD	22131
NESC0369_11.007	UPD SOURCE PROGRAM (F4) EBCD	1325
NESC0369_11.008	UPD SOURCE PROGRAM (ASSEMBLER) EBCD	203
NESC0369_11.009	UPD INPUT DATA (FORTRAN PART)	20
NESC0369_11.010	UPD INPUT DATA (ASSEMBLER PART)	14
NESC0369_11.011	UPD DD CARDS (FORTRAN PART)	32
NESC0369_11.012	UPD DD CARDS (ASSEMBLER PART)	18
NESC0369_11.013	UPD OUTPUT (SELECTED FORTRAN) EBCD	1650
NESC0369_11.014	UPD OUTPUT (SELECTED ASSEMBLER) EBCD	5391
NESC0369_11.015	UPD PRINTED OUTPUT (FORTRAN PART)	95
NESC0369_11.016	UPD PRINTED OUTPUT (ASSEMBLER PART)	92
NESC0369_11.017	RELAP4/M5 OVERLAY CARDS	87
NESC0369_11.018	RELAP4/M5 JCL	43
NESC0369_11.019	RELAP4/M5 STEAM TABLE(BIN,RECFM=VS,BLKSIZE=	79
NESC0369_11.020	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 1	164
NESC0369_11.021	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 2	8
NESC0369_11.022	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 3	8
NESC0369_11.023	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 4	8
NESC0369_11.024	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 5	441
NESC0369_11.025	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 6	45
NESC0369_11.026	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 7	229
NESC0369_11.027	RELAP4/M5 SAMPLE PROBLEM INPUT DATA (CASE 8	257
NESC0369_11.028	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 1)	1735
NESC0369_11.029	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 2)	356
NESC0369_11.030	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 3)	238
NESC0369_11.031	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 4)	339
NESC0369_11.032	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 5)	2867
NESC0369_11.033	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 6)	990
NESC0369_11.034	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 7)	2213
NESC0369_11.035	RELAP4/M5 SAMPLE PRINTED OUTPUT (CASE 8)	3442
NESC0369_11.036	PLOT SOURCE PROGRAM (F4)	2190
NESC0369_11.037	PLOT BUFIO ROUTINE OBJECT DECK	6
NESC0369_11.038	PLOT JCL	61
NESC0369_11.039	PLOT SAMPLE PROBLEM	9

File name	File description	Records
NESC0369_19.001	RELAP-4/6-KFK INFORMATION FILE	70
NESC0369_19.002	RELAP-4/6-KFK JCL FOR IMPLEMENT. & EXEC.	266
NESC0369_19.003	RELAP-4/6-KFK SOURCE (FORTRAN-4)	66829
NESC0369_19.004	PRELOAD SOURCE (FORTRAN-4)	1113
NESC0369_19.005	UPD SOURCE (FORTRAN-4)	1328
NESC0369_19.006	UPD SOURCE (ASSEMBLER)	340
NESC0369_19.007	ENVIRONMENTAL SUBROUTINES SOURCE (FORTRAN-4)	1415
NESC0369_19.008	ENVIRONMENTAL SUBROUTINES SOURCE (ASSEMBLER)	1697
NESC0369_19.009	RELAP-4/6-KFK INPUT FOR TEST CASE	179
NESC0369_19.010	RELAP-4/6-KFK BASIC LINK-EDIT DIRECTIVES	302
NESC0369_19.011	WATER PROPERTIES FILE	79
NESC0369_19.012	PRELOAD OUTPUT OF TEST CASE	211
NESC0369_19.013	RELAP-4/6-KFK LINKEDIT OUTPUT	57
NESC0369_19.014	RELAP-4/6-KFK OUTPUT OF TEST CASE	1890
NESC0369_19.015	PRINTL SOURCE (FORTRAN-4)	17