1. NAME AND TITLE

LTC: LMR Transient Calculation Code System (version 5).

2. CONTRIBUTOR

School of Nuclear Engineering, Purdue University, West Lafayette, Indiana, and Argonne National Laboratory, Argonne, Illinois.

3. CODING LANGUAGE AND COMPUTER/OPERATING SYSTEM

Microsoft GW-Basic and Quick Basic 4.5;IBM PC.

4. NATURE OF PROBLEM SOLVED

The Liquid Metal Reactor (LMR) may undergo an unscrammed Transient Over-Power (TOP) or a Loss of Heat Sink (LOHS) type of accident involving power, temperature, and reactivity changes. The LTC (LMR Transient Calculation) Program calculates the time dependent reactor temperatures, reactivities, and power of the LMR after the initiation of the accident. A printout of the results including the input table of data is offered after the program run. No graphics are used in the program and the LTC.EXE (Quick Basic compiled) can make use of a math co-processor if available (GW Basic doesn't).

5. METHOD OF SOLUTION

The LTC program description including the physics and math involved are contained within the referenced document ANL-RE-91/2 vol. 2. A transient model applying point kinetics and a prompt jump approximation (PJA) is used as the mathematical model for the LTC program. A source multiplication formula, representing an implicit solution of the PJA version of the kinetics equation calculates the relative fission power. Both prompt and delayed neutron sources are included (See section 1. of ref. document above).

6. RESTRICTIONS OR LIMITATIONS

The Loss of Flow (LOF) accident is not available in this version. Dimensions in the input data file are restricted when the LTC program is run using GW-BASIC, but not LTC.EXE (Quick Basic Compiled). The execution time of LTC is minimal, a PC 386/33 MHz ran the sample program in 8 seconds.

7. TYPICAL RUNNING TIME

The running time is dependent on the type of hardware (PC XT vs. PC 486) used, but generally a calculation and full printout takes a few minutes.

8. COMPUTER HARDWARE REQUIREMENTS

LTC executes on a IBM PC personal computer equipped with a math co-processor and a parallel printer (Epson, IBM, or HP laserjet). Any PC or compatible using a parallel printer would be adequate, a math co-processor is not necessary to run LTC.EXE, but would be used if present. The entire software package with examples will require only 352 kbytes of space on the hard drive.

9. COMPUTER SOFTWARE REQUIREMENTS

DOS 3.3 or higher, with 640 k RAM. The source file (LTC.BAS) was compiled and linked used Microsoft Quick Basic version 4.5.

10. REFERENCES

K. O. Ott, "A Fast Reactor Transient Analysis Methodology for PCs: Vol. 1, The Computational Model," ANL/RE-91/2 Vol. 1 (October 1991).

K. O. Ott, "A Fast Reactor Transient Analysis Methodology for PCs: Vol. 2, LTC Program Manual," ANL/RE-91/2 Vol. 2 (October 1991).

K. O. Ott, "A Fast Reactor Transient Analysis Methodology for Personal Computers," Nucl. Sci. and Engg. 113, 122-135 (1993).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and 1 DS/HD (1.2 MB) diskette which contain the GW basic and Quick Basic source files, compiled Quick Basic executable, and sample input/output data files for use with examples, a packing list, and a readme.1st help file. The file README.1ST describes the installation and operation of the code.

12. DATE OF ABSTRACT

April 1993.