NESC0784 DSNP.

1. NAME OR DESIGNATION OF PROGRAM:  DSNP.

3. DESCRIPTION OF PROBLEM OR FUNCTION

DSNP (Dynamic Simulator for Nuclear Power-Plants) is a system of programs and data files by which a nuclear power plant, or part thereof, can be simulated. The  acronym DSNP is used interchangeably for the DSNP language, the DSNP libraries, the DSNP precompiler, and the DSNP document generator.

The DSNP language is a special-purpose, block-oriented digital- simulation language developed to facilitate the preparation of dynamic simulations of a large variety of nuclear power plants. It is a user-oriented language that permits the user to prepare simulation programs directly from power plant block diagrams and flow charts by recognizing the symbolic DSNP statements for the appropriate physical components and listing these statements in a logical sequence according to the flow of physical properties in the simulated power plant.

Physical components of nuclear power plants are represented by functional blocks, or modules. Many of the more complex components are represented by several modules. The nuclear reactor, for example, has a kinetic module, a power distribution module, a feedback module, a thermodynamic module, a hydraulic module, and a radioactive heat decay module. These modules are stored in DSNP libraries in the form of a DSNP subroutine or function, a block of statements, a macro, or a combination of the above. Basic functional blocks such as integrators, pipes, function generators, connectors,  and many auxiliary functionsrepresenting properties of materials used in nuclear power plants are also available.

The DSNP precompiler analyzes the DSNP simulation program, performs the appropriate translations, inserts the requested modules from the library, links these modules together, searches necessary data files, and produces a simulation program in FORTRAN. FORTRAN is considered to be a subset of DSNP and can be inserted anywhere in the simulation program without restriction.

I/O statements can be located anywhere in the program in arbitrary sequence. No formatting is required and the listed variables are printed at user-defined intervals in an easy-to-read tabular form.

4. METHOD OF SOLUTION

The mathematical models used vary from one component module to another. Mostly, however, lumped parameter models were used. The differential equations produced by each component module are solved by a centralized integration scheme. The various loops of the power plant can be solved with different integration schemes using different time-step sizes. Any of eight integration schemes including Adams' 2nd-order, Euler, Milne's 5th-  order predictor-corrector, Runge-Kutta 4th-order, Simpson 3rd-order, trapezoidal, and the method used in CSMP III can be selected. DSNP is written in double-precision, and all units are SI metric.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

Only overall plant transients can be studied since most models are based on the lumped  parameter approximation. For detailed transients inside the core, heat exchanger, or any other component, a more sophisticated library will be developed in the future.

6. TYPICAL RUNNING TIME

Running time is a function of the size of the simulation. The precompilation time is approximately 50 seconds per  1000 FORTRAN statements.

NEA-DB executed the test cases included in this package  on an IBM 3090 computer. CPU execution times varied from 20 seconds  to 3 minutes.

7. UNUSUAL FEATURES OF THE PROGRAM:

8. RELATED AND AUXILIARY PROGRAMS:

10. REFERENCES

- D. Saphier,
  A Simulation Language for  Nuclear Power Plants, Proceedings of
  the 1977 Summer Computer Simulation Conference, July 18-20, 1977,
  pp.  353-358,
  AFIPS Press, Montvale, New Jersey, 1977.

- J.T. Madell:
DSNP User' Letter Vol.1, No. 1  (October 1981)
- J.T. Madell:
DSNP User' Letter Vol.1, No. 2  (December 1981)
- Fauske and Associates, Inc.:
DSNP User' Letter Vol.2, No. 1  (November 1982)
- Fauske and Associates, Inc.:
DSNP User' Letter Vol.3, No. 2  (July 1983)
- D. Saphier:
MINIEDITOR, ANL-77-18  (August 1977)
- D. Saphier:
The Simulation Language of DSNP:
Dynamic Simulator for Nuclear Power-Plants (User Manual)
ANL-CT-77-20, Rev. 3.4  (December 1983) (on magnetic tape)
- D. Saphier:
The Precompiler for the DSNP:
Dynamic Simulator for Nuclear Power-Plants
ANL-CT-77-21, Rev. 02 (September 1978) (on magnetic tape)
- D. Saphier:
The Level-One Modules Library for DSNP:
Dynamic Simulator for Nuclear Power-Plants (Volume 1)
ANL-CT-77-22 Rev. EBR-3.4, Vol. 1  (November 1983) (on magnetic tape)
- D. Saphier:
The Level-One Modules Library for DSNP:
Dynamic Simulator for Nuclear Power-Plants (Volume 2)
ANL-CT-77-22 Rev. EBR-3.4, Vol. 2  (January 1984) (on magnetic tape)
- P. Johnson:
DSNP Tape Description, NESC Note 86-77  (July 15, 1986)

11. MACHINE REQUIREMENTS

250K bytes of storage are required to compile and translate a typical power plant simulation program. Six scratch  files require disk or fast magnetic tape storage and a permanent library file unit is used. All sample problems were executed in a 250K byte or smaller region.

To execute the test cases included in this package on an IBM 3090 computer, main storage requirements varied from 1000K to 1300K bytes depending on the case.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  MVS.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

   The
machine-readable documentation on files 25-28 of the transmittal tape was prepared using the proprietary Watcom Products, Inc. SCRIPT text-processing system.

15. NAME AND ESTABLISHMENT OF AUTHORS

                 D. Saphier
                 Department of Applied Mathematics
                 Soreq Nuclear Research Centre
                 Yavneh, Israel

                 J. Madell
                 Fauske & Associates, Inc.

                 E. Dean
                 EBR-II Division
                 Argonne National Laboratory

File name	File description	Records
NESC0784_02.001	Information file	85
NESC0784_02.002	JCL for precompiler and simulation program	106
NESC0784_02.003	precompiler FORTRAN source	2757
NESC0784_02.004	level-1 library DSNP and FORTRAN source	5257
NESC0784_02.005	level-2 library DSNP and FORTRAN source	486
NESC0784_02.006	default data for all the sample problems	25
NESC0784_02.007	sample problem input # 1	107
NESC0784_02.008	sample problem input # 2	71
NESC0784_02.009	sample problem input # 3	115
NESC0784_02.010	sample problem input # 4	91
NESC0784_02.011	sample problem input # 5	509
NESC0784_02.012	sample problem input # 6	147
NESC0784_02.013	sample problem input # 7	207
NESC0784_02.014	sample problem input # 8	160
NESC0784_02.015	sample problem input # 9	277
NESC0784_02.016	sample problem input # 10	107
NESC0784_02.017	sample problem print # 1	907
NESC0784_02.018	sample problem print # 2	2723
NESC0784_02.019	sample problem print # 3	659
NESC0784_02.020	sample problem print # 4	961
NESC0784_02.021	sample problem print # 5	4877
NESC0784_02.022	sample problem print # 6	1040
NESC0784_02.023	sample problem print # 7	869
NESC0784_02.024	sample problem print # 8	723
NESC0784_02.025	sample problem print # 9	1292
NESC0784_02.026	sample problem print # 10	1103
NESC0784_02.027	user manual	4004
NESC0784_02.028	precompiler manual	8656
NESC0784_02.029	library manual vol. 1	6576
NESC0784_02.030	library manual vol. 2	10785