EXPERIMENTAL STUDY ON THE EFFECT OF NON-UNIFORM INLET VELOCITY PROFILE ON INTERNAL COOLING IN RECTANGULAR CHANNELS WITH MULTI-FEATURES

摘要

Experiments were conducted to investigate the overall thermal performance of rectangular channels with a non-uniform inlet velocity profile. Two test sections with multiple internal cooling features had been used. One test section was implemented with two circular staggered pin-fin arrays with different pin diameters. The other one was implemented with a combination of a staggered pin-fin array and a perforated blockage array. The average surface heat transfer coefficient of the pedestal and perforated blockage and the local distribution of heat transfer coefficient on endwall were measured by the lumped capacitance method and transient liquid crystal method, respectively. The pressure drop across each array was measured. The heat transfer coefficients were measured over the Reynolds number range from 9,000 to 17,000. The spanwise pitches of the upstream pin-fin arrays were 2.33 and 4.66 for the channel with the multiple pin-fin array and the channel with perforated blockage, respectively. The effect of a non-uniform velocity profile on local heat transfer pattern and row-resolved heat transfer coefficient has been investigated.