J032011 Thermal fatigue of pipes induced by fluid temperature change : (4) Effects of mesh and inlet boundary conditions on CFD for thermal load evaluation

Abstract

Thermal fatigue crack may initiate at a mixing tee where high and low temperature fluids flow in and mix. In order to prevent piping failure caused by thermal fatigue, an evaluation procedure of fluid temperature fluctuation at mixing tee using numerical simulation has been developed in the Japan Ageing Management Program for System Safety (JAMPSS) supported by the Nuclear Regulation Agency in Japan. The developing process and the current research issues are discussed in this paper regarding to the estimation method of temperature fluctuation in pipe wall using numerical simulations. This paper also describes the effect of grid fineness and inlet conditions on the simulated temperature fluctuation downstream from a T-junction.