VISA-II: a computer code for predicting the probability of reactor pressure vessel failure
The VISA-II (Vessel Integrity Simulation Analysis code was originally developed as part of the NRC staff evaluation of pressurized thermal shock. VISA-II uses Monte Carlo simulation to evaluate the failure probability of a pressurized water reactor (PWR) pressure vessel subjected to a pressure and thermal transient specified by the user. Linear elastic fracture mechanics methods are used to model crack initiation and propagation. Parameters for initial crack size and location, copper content, initial reference temperature of the nil-ductility transition, fluence, crack-initiation fracture toughness, and arrest fracture toughness are treated as random variables. This report documents an upgraded version of the original VISA code as described in NUREG/CR-3384. Improvements include a treatment of cladding effects, a more general simulation of flaw size, shape and location, a simulation of inservice inspection, an updated simulation of the reference temperature of the nil-ductility transition, and treatment of vessels with multiple welds and initial flaws. The code has been extensively tested and verified and is written in FORTRAN for ease of installation on different computers. 38 refs., 25 figs.
- Research Organization:
- Pacific Northwest Lab., Richland, WA (USA)
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 6027268
- Report Number(s):
- NUREG/CR-4486; PNL-5775; ON: TI86009173
- Country of Publication:
- United States
- Language:
- English
Similar Records
VISA: a computer code for predicting the probability of reactor pressure-vessel failure. [PWR]
New techniques for modeling the reliability of reactor pressure vessels
Related Subjects
210200 -- Power Reactors
Nonbreeding
Light-Water Moderated
Nonboiling Water Cooled
22 GENERAL STUDIES OF NUCLEAR REACTORS
220900* -- Nuclear Reactor Technology-- Reactor Safety
36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
COMPUTERIZED SIMULATION
CONTAINERS
CRACK PROPAGATION
CRACKS
FAILURES
FORTRAN
FRACTURE MECHANICS
MATHEMATICAL MODELS
MECHANICS
NEUTRON FLUENCE
PRESSURE VESSELS
PROBABILITY
PROGRAMMING LANGUAGES
PWR TYPE REACTORS
REACTORS
SIMULATION
STRESSES
WATER COOLED REACTORS
WATER MODERATED REACTORS