NESC0245 RTS.

1. NAME OR DESIGNATION OF PROGRAM:  RTS.

3. NATURE OF PHYSICAL PROBLEM SOLVED

RTS solves the reactor kinetic equations in the delay-neutron regime by means of direct numerical evaluation of transient behaviour. It solves the general non- equilibrium kinetics problem with arbitrary reactivity variation and extraneous sources, the customary equilibrium solution being a special case of the general solution.

4. METHOD OF SOLUTION

The reactor kinetic equations are reduced to an  integral form convenient for explicit numerical solution, involving  no approximations beyond the usual space-independent assumption. RTS performs the numerical evaluation. The characteristic roots and residues which arise in this method of solution have been tabulated  for each of the main fissile species. Analytic or point-function reactivity variation may be introduced, together with constant or time-varying reactivity compensation, and the resulting neutron density or power response, total energy release, and compensated reactivity computed as time-dependent functions.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

When input reactivity cannot be readily expressed analytically, it may be expressed numerically as a point function of time. The programme as presently  written can accommodate in a single run up to 500 data points, which need not be equally spaced in time.

6. TYPICAL RUNNING TIME

Approximately 1500 integrations per minute for constant time intervals, approximately 10 minutes per curve for uncompensated problems, approximately 30 minutes per curve for compensate problems, on the IBM 704. Typical running times on the IBM 7094 are approximately an order of magnitude faster.

7. UNUSUAL FEATURES OF THE PROGRAM

Complete output and input dumps available for problem continuation as required. If more than 500 data points are required to specify input reactivity, the problem can be continued by employing a stop-start feature, whereby sets of  data points are treated in sequence. Print out flexibility as described in references.

8. RELATED AND AUXILIARY PROGRAMS

RTR and LASL polynomial SOLVER subroutine, input reactivity function fit subroutine.

10. REFERENCES

- G.R. Keepin and C.W. Cox:
  General Solution of the Reactor Kinetic Equations.
  Nuclear Science and Engineering, Vol.8, No. 6, December 1960.
- Reactor Kinetics and Control.
  AEC Symposium Series Number 2. USAEC Division of Technical Information, 1964
- The Technology of Nuclear Reactor Safety, Vol. 1, Reactor Physics and Control.
  The Mit Press, Cambridge MA, 1964
- G.R. Keepin:
  Physics of Nuclear Kinetics.
  Addison Wesley, Reading MA, 1965

11. MACHINE REQUIREMENTS:  32k with 2 tapes units.

13. SOFTWARE REQUIREMENTS: OPERATING SYSTEM OR MONITOR UNDER WHICH PROGRAM IS EXECUTED

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

ANY OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

15. NAME AND ESTABLISHMENT OF AUTHOR

        G.R. Keepin
        Los Alamos Scientific Laboratory
        P.O. Box 1663
        Los Alamos, New Mexico 87544

File name	File description	Records
NESC0245_01.001	SOURCE & DATA FORTRAN 4	659
NESC0245_01.002	OUTPUT FORTRAN 4	1128