Validation on a water leak rate calculation module of AWACS by gas blowdown tests; Report No.1 : Study of water leak rate from a failed heat transfer tube in an LMFBR's SG

Hiroi, Hiroshi*; Miyake, Osamu; not registered

The computer code for a large leak sodium-water reaction in an LMFBR SG-SWACS-has been developed by PNC. The most important parameter of sodium-water reaction phenomena is the water leak rate from a failed tube. To validate the calculation module of water leak rate, named SWAC-11, the thrust forces caused by fluid discharge from a pipe were measured and compared with the computer code. This report describes a model of the thrust fonce calculation, the measuring method of the thrust force, and comparisons between gas blowdown tests and calculational results by SWAC-11. Major conclusions are as follows : (1)Compared with analytical solutions and experimental data, the numerical calculation method of SWAC-11 was validated. (2)The short term transient of thrust force could be measured using the spring-mass model. (3)Compared with analytical solutions, the "cell center approximation" was found to be good as a thrust force calculation model of SWAC-11. High temperature and water blowdown tests using this measuring method will be described in the No.2 report.