高レイノルズ数エルボ管流れにおける熱伝達のLES解析

抄録

Flow accelerated corrosion (FAC) is one of the causes for wall thinning mechanisms in carbon steel pipes. Prediction of geometry factor is the key elements for estimation of FAC. Geometry factor is defined as the ratio of wall mass transfer coefficient in the piping systems such as elbow to that in a straight pipe. In this study, geometry factor of the elbow pipe is computed by using large eddy simulation (LES) for Re=45000, 180000, 540000. In order to simulate the mass transfer coefficient, we adopt the analogy between mass transfer and heat transfer. Geometry factor around outside of the elbow affected by high velocity drift decreased with increasing Re. On the other hand, maximum value of geometry factor around inside caused by unsteady flow is independent of Re.