RSICC CODE PACKAGE PSR-406

1. NAME AND TITLE

FRANTIC3: Time-Dependent Reliability Analysis.

2. CONTRIBUTORS

Brookhaven National Laboratory, Upton, New York, through the Energy Science and Technology Software Center, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV (CDC FTN 4.8); CDC7600 (P00406CDCMF00).

4. NATURE OF PROBLEM SOLVED

FRANTIC3 was developed to evaluate system unreliability using time-dependent techniques. The code provides two major options: to evaluate standby system unavailability or, in addition to the unavailability, to calculate the total system failure probability by including both the unavailability of the system on demand as well as the probability that it will operate for an arbitrary time period following the demand. The FRANTIC time-dependent reliability models provide a large selection of repair and testing policies applicable to standby or continuously operating systems consisting of periodically tested, monitored, and non-repairable (non-testable) components. Time-dependent and test frequency dependent failures, as well as demand stress related failure, test-caused degradation and wear-out, test associated human errors, test deficiencies, test override, unscheduled and scheduled maintenance, component renewal and replacement policies, and test strategies can be prescribed. The conditional system unavailabilities associated with the downtimes of the user specified failed component are also evaluated. Optionally, the code can perform a sensitivity study for system unavailability or total failure probability to the failure characteristics of the standby components.

5. METHOD OF SOLUTION

FRANTIC3 uses a set of analytical equations for component unavailabilities and failure intensities with exponential and Weibull failure time distributions for constant test and duration times. The FRANTIC code determines the state (test, repair, or between test) of each component at each time point and selects the appropriate component unavailability model depending on the state. Using the appropriate logical relationships among the unavailabilities of individual components, the system unavailability (or total failure probability) is also calculated at these time points. Then, the system average unavailability (or total failure probability) is calculated by integrating the instantaneous unavailability (or total failure probability) over the standby time period. A Boolean equation is specified by the user via the SYSCOM subroutine to define the system unavailability functions. The system failure occurrence rate function needed for the system unreliability evaluation is user defined via the SYSOP subroutine.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

NESC executed the sample problem in 55 seconds on a CDC CYBER875 in 1987.

8. COMPUTER HARDWARE REQUIREMENTS

254,000 (octal) words of memory on CDC computers.

9. COMPUTER SOFTWARE REQUIREMENTS

FRANTIC3 was run under the SCOPE 2.1.5 operating system.

10. REFERENCES

a) Included in document:

FRANTIC3, NESC No. 766, FRANTIC3 Tape Description and Implementation Information, NESC Note 87-89 (August 31, 1987).

T. Ginzburg and J. T. Powers, "FRANTIC III - A Computer Code for Time-Dependent Reliability Analysis (User's Manual)," BNL A-3230 Technical Report (August 20, 1986).

b) Background information:

W. E. Veseley and F. F. Goldberg, "FRANTIC, A Computer Code for Time Dependent Unavailability Analysis," NUREG-0193 (October 1977).

A3230(4/1/84)(Methodology).

11. CONTENTS OF CODE PACKAGE

Included in the package are the referenced documents in (10.a) and a diskette containing a self-extracting compressed DOS file, which includes source code, control file, readme file, and input/output files.

12. DATE OF ABSTRACT

May 1999.

KEYWORDS: REACTOR SAFETY