NEA-0575 STESTA.

1. NAME OR DESIGNATION OF PROGRAM:  STESTA.

3. NATURE OF PHYSICAL PROBLEM SOLVED

STESTA is used to calculate steady-state profiles of the state variables of thermohydraulic piping networks. It can be applied to hydrodynamically or thermodynamically coupled or uncoupled multi-loop complex piping networks, filled with any single-phase or  two-phase fluid.
Hydraulic losses are considered, continously as well as resulting from abrupt geometry changes. For the analysis of closed-loop behaviour, the code contains a pump model based on (q,h)- characteristics.
To the IBM version the possibility of specifying the hydraulic dia-  meter for the volumes and junctions was added. This enables the treatment of annular sections, bundles of pipes, contracted multiple loops.

4. METHOD OF SOLUTION

The code considers the thermohydraulic steady-state balance equations for momentum, mass and energy and iterates them for consistent state profiles for pressure, temperature and mass flow, based on boundary values needed for every uncoupled sub-system. Sources and sinks of heat and mass fluxes are also taken into  account.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The present version of STESTA has the following restrictions:
Maximum number of volumes                           50
Maximum number of junctions                         50
Maximum number of distinct hydrodynamic  loops       5
Maximum number of different fluid media              5
Maximum number of different pumps                    5
Maximum number of different pump characteristics     5
Any of these restrictions can be extended by internal adaption of the respective DIMENSION statements.

6. TYPICAL RUNNING TIME

To compile and execute the sample problem: 14 seconds of CPU time (CYBER 175). NEA-DB executed the test case on IBM 3033 in 17 seconds.

7. UNUSUAL FEATURES OF THE PROGRAM

STESTA was written to calculate the steady-state profiles required by transient programs such as RELAP4 and WHAM. The code allows a free-formatted data input in either 'American' or SI-units and gives extensive input assistance,  especially in the case of systematically structured  networks.

8. RELATED AND AUXILIARY PROGRAMS

The basic equations are tightly fit to the respective equations in the RELAP4 code, so a full compatibility  is accomplished.

- H.J. Schittke:
  Input Description for 'STESTA'
  17.1.1979. (in German).
- H.J. Schittke:
  Input Description for 'STESTA'
  17.1.1979. (in German).

11. MACHINE REQUIREMENTS

100000 (octal) words (CDC computers).
300 Kbytes on IBM 3033.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  NOS1 (CDC CYBER 175). OS370/033 VS2 03.8G (IBM 3033).

15. NAME AND ESTABLISHMENT OF AUTHOR

H.J. Schittke
Industrianlagen-Betriebsgesellschaft MBH
Einsteinstrasse
D-8012 Ottobrunn
The Federal Republic of Germany

File name	File description	Records
NEA0575_01.001	INFORMATION , JCL	22
NEA0575_01.002	SOURCE (F4,EBCDIC)	3739
NEA0575_01.003	INPUT DATA FOR S. P.	26
NEA0575_01.004	PRINTED OUT OF S. P.	514

File name	File description	Records
NEA0575_02.003	STESTA INFORMATION FILE	63
NEA0575_02.004	STESTA, SOURCE CARD IMAGES (FORTRAN-4)	3919
NEA0575_02.006	STESTA, INPUT FOR SAMPLE CASE	34
NEA0575_02.007	STESTA, PRINTED OUTPUT OF SAMPLE CASE	724
NEA0575_02.008	STESTA, JCL TO RUN SAMPLE CASE	69