RSICC CODE PACKAGE PSR-474

1. NAME AND TITLE

ORCENT 2: Code System for Analysis of Steam Turbine Cycles Supplied by Light Water Reactors.

2. CONTRIBUTORS

Oak Ridge National Laboratory, Oak Ridge, Tennessee through the NEA Data Bank, Issy-les-Moulineaux, France.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; IBM 360/370 (P00474I303300).

4. NATURE OF PROBLEM SOLVED

ORCENT-2 performs heat and mass balance calculations at valves-wide-open design conditions, maximum guaranteed rating conditions, and an approximation of part-load conditions for steam turbine cycles supplied with throttle steam, characteristic of contemporary light-water reactors. The program handles both condensing and back-pressure turbine exhaust arrangements. Turbine performance calculations are based on the General Electric Company method for 1800-rpm large steam turbine- generators operating with light-water-cooled nuclear reactors. Output includes all information normally shown on a turbine-cycle heat balance diagram.

5. METHOD OF SOLUTION

The turbine performance calculations follow the procedures outlined in General Electric report GET-6020. ORCENT-2 utilizes the 1967 American Society of Mechanical Engineers (ASME) formulations and procedures for calculating the properties of steam, adapted for ORNL use by D.W. Altom.

6. RESTRICTIONS OR LIMITATIONS

Maxima of 12 feed-water heaters. Five moisture removal stages in the low-pressure turbine section. ORCENT-2 is limited to 1800-rpm tandem-compound turbine-generators with single- or double-flow high pressure sections and one, two, or three double-flow low-pressure turbine sections. Steam supply for LWR cycles should be between 900 and 1100 psia and slightly wet to 100 degrees F of initial superheat. Generator rating should be greater than 100 MVA.

7. TYPICAL RUNNING TIME

Execution time for one valves-wide-open case followed by one maximum guaranteed case is approximately 5 seconds on the IBM 360/91. NESC compiled and executed the sample problems in less than 30 CPU seconds on an IBM 3033.

8. COMPUTER HARDWARE REQUIREMENTS

ORCENT-2 was developed on IBM 360/370 computers. Approximately 210K bytes of storage were needed for execution of the sample problems on an IBM 3033.

9. COMPUTER SOFTWARE REQUIREMENTS

ORCENT requires a FORTRAN-IV compiler and was developed under IBM OS/360, 370. It was tested at the NEA Data Bank on and IBM 3033 running OS/VS2 with the H-extended compiler. The code was not tested when it was transmitted to RSICC in February 2000.

10. REFERENCES

a) Included in document:

L.C. Fuller, "User's Instructions for ORCENT II - A Digital Computer Program for the Analysis of Steam Turbine Cycles Supplied by Light-Water- Cooled Reactors," ORNL/TM-6525 (February 1979).

b) Background information:

F.G. Baily, J.A. Booth, K.C. Cotton, and E.H. Miller, "Predicting the Performance of 1800-rpm Large Steam Turbine Generators Operating with Light-Water-Cooled Reactors," GET-6020 (February l973).

R.B. McClintock and G.J. Silvestri, "Formulations and Iterative Procedures for the Calculation of Properties of Steam American Society of Mechanical Engineers,"New York (1967).

NESC, "ORCENT2, NESC No. 703, ORCENT2 Sample Problem Output," NESC Note 80-08 (December 5, 1979).

11. CONTENTS OF CODE PACKAGE

Included in the package are the referenced document in (10.a) and one DS/HD diskette which includes the source and test case.

12. DATE OF ABSTRACT

April 2000.

KEYWORDS: LWR; PWR