Pulsating flow in circular pipes — the analysis of thermal stresses

Abstract

Flow pulsation in externally heated pipes generates a pulsating temperature field, which, in turn results in oscillating thermal stresses across the pipe wall. In the present study, pulsating flow inside a circular pipe, which is externally heated, is considered. The flow and temperature fields are computed numerically using a control volume approach. The resulting thermal stresses across the pipe wall due to temperature variation in the transverse direction are computed. Pressure pulsation at the pipe inlet is employed to produce the flow pulsation. The simulations are extended to include different pipe lengths, pipe diameters and pipe thickness. It is found that pipe diameter has a significant effect on the effective stress levels; in which case, the amplitude of the oscillation in stress levels across the pipe wall reduces considerably with increasing pipe diameter. Moreover, the effect of Reynolds number is more pronounced at mid and outlet planes such that increasing Reynolds number amplifies the amplitude of stress levels in the pipe.