1. NAME AND TITLE

ALKASYS: A Computer Program For Studies of Rankine-Cycle Space Nuclear Power Systems.

2. CONTRIBUTOR

Oak Ridge National Laboratory, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

BASIC; IBM PC.

4. NATURE OF PROBLEM SOLVED

The program ALKASYS is used for the creation of design concepts of multimegawatt space nuclear power systems that employ potassium Rankine power conversion cycles.

5. METHOD OF SOLUTION

ALKASYS calculates performance and design characteristics and mass estimates for the major subsystems composing the total power system. Design and engineering performance characteristics are determined by detailed engineering procedures rather than by empirical algorithms. Mass estimates are developed using basic design principles augmented in some cases by empirical coefficients determined from the literature. The reactor design is based on a fast spectrum, metallic-clad rod fuel element containing UN pellets.

6. RESTRICTIONS OR LIMITATIONS

ALKASYS was developed primarily for the analysis of systems with electric power in the range from 1000 to 25,000 kW(e) and full-power life from 1 to 10 years. The program should be used with caution in systems that are limited by heat flux (which might indicate need for extended surfaces on fuel elements) or criticality (which might indicate the need for other geometries or moderators).

7. TYPICAL RUNNING TIME

The sample case using the direct cycle took about 5 minutes on an IBM PC/XT under the DOS operating system.

8. COMPUTER HARDWARE REQUIREMENTS

IBM PC and compatibles.

9. COMPUTER SOFTWARE REQUIREMENTS

The code was written in IBM BASIC and tested under PC-DOS (IBM PC). An ASCII file produced by the BASIC interpreter is included.

10. REFERENCE

J. C. Moyers, and J. P. Nichols, "ALKASYS, A Computer Program For Studies of Rankine-Cycle Space Nuclear Power Systems," ORNL/TM-10427 (September 1987).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one (360 K) DOS diskette.

12. DATE OF ABSTRACT

November 1990.