Analytical Studies of Blowdown Thrust Force and Elastic-Plastic Behavior of Pipe at Pipe Rupture Accident

When high-temperature and high-pressure water is ejected from pipe, a blowdown thrust force will act on the pipe and it will cause pipe movement. The analytical methods of blowdown thrust force and pipe movement are presented in the paper. The equation of momentum conservation is used to calculate the blowdown thrust force, together with the results of the thermal-hydraulic analysis code RELAP4/MOD6. The finite element method is used to calculate the dynamic movement of pipe. The equations for calculating the maximum strain at the outer surface of pipe are derived by assuming the static equilibrium condition. The analytical results are compared with experimental ones to verify the analytical methods presented here.