PSR-0533 SQUIRT 1.1.

1. NAME OR DESIGNATION OF PROGRAM:  SQUIRT 1.1

3. DESCRIPTION OF PROGRAM OR FUNCTION

The SQUIRT (Seepage Quantification of Upsets In Reactor Tubes) software is predicts leakage rate and area of crack opening for cracked pipes in nuclear power plants. In all cases, the fluid in the piping system is assumed to be water at a given temperature and pressure. The development of the SQUIRT computer model enables licensing authorities and industry users to conduct leak-rate evaluations for leak-before-break applications in a more efficient manner.
  
This Windows Version 1.1 is based on SQUIRT Version 2.4a with modifications and enhancements for single-phase liquid module, single-phase steam module and extremely tight cracks. Other enhancements include an option to account for the effect of weld residual stresses on the crack-opening displacements and associated leak rate, an option to incorporate the corrections to crack morphology parameters for tight cracks based on methodology proposed in NUREG/CR-6004 and new default crack morphology parameters for Primary Water Stress Corrosion Cracking (PWSCC).

4. METHODS

The fracture mechanics analysis performed by SQUIRT is based on a modi-fied version of the NRCPIPE computer program (Brust, 1987). The SQUIRT program uses a modified from of the Henry-Fauske model for the thermal-hydraulics analysis together with Elastic-Plastic Fracture Mechanics using GE/EPRI and LBB.ENG2 methods for crack opening analysis.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The current version of SQUIRT does not have a transitional two-phase flow model to handle pipe cracks with depth (pipe wall thickness) to hydraulic-diameter ratios between 0.5 and 15. It can only predict leakage flow rates in very tight cracks (crack depth to hydraulic-diameter ratios greater than 15) or in orifice-type cracks (crack depth to hydraulic-diameter ratios less than 0.5).

6. TYPICAL RUNNING TIME

Run time requirements depend highly on the speed of PC but most runs require less than 2 minutes.

10. REFERENCES

- S. Rahman and others:
Refinement and Evaluations of Crack-Opening-Area Analysis for Circumferential Through-Wall Cracks in Pipes, NUREG/CR-6300 (April 1995).
- D. D. Paul and others:
Evaluation and Refinement of Leak-Rate Estimation Models, NUREG/CR-5128, Rev. 1 (June 1994).

- SQUIRT: Seepage Quantification of Upsets In Reactor Tubes, User's Manual,
Windows Version 1.1, Battelle Informal Report (March 24, 2003).
- S. Rahman, N. Ghadiali, D. Paul, and G. Wilkowski:
Probabilistic Pipe Fracture Evaluations for Leak-Rate-Detection Applications,
NUREG/CR-6004 (April 1995).

11. HARDWARE REQUIREMENTS:  SQUIRT runs on Pentium computers.

13. SOFTWARE REQUIREMENTS

SQUIRT 1.1 runs on Windows-based Pentium computers. Executables created with Microsoft Quick Basic and Visual Basic 6.0 are included in the package.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:  Source files are not included.

15. NAME AND ESTABLISHMENT OF AUTHORS

Contributed by:
                Radiation Safety Information Computational Center
                Oak Ridge National Laboratory
                Oak Ridge, Tennessee, U. S. A.
  
Developed by:   Battelle Memorial Institute, Columbus, Ohio, USA

self-installing Windows: executables, data files and test cases
Electronic documentation