Measurement of Heat Transfer Rate on Backward-Facing Steps at Hypersonic Mach Number

摘要

Two backward-facing models with step heights of 2 and 3 mm are used to measure the convective surface heatntransfer rates by using platinum thin-film gauges, deposited on Macor inserts. Heat transfer rates have beenntheoretically calculated along the flat plate portion of a model using the Eckert reference temperature method. Thenexperimentally determined surface heat transfer rate distributions are compared with theoretical and numericalnestimations. Experimental heat flux distribution over a flat plate model showed good agreement with the referencentemperature method at stagnation enthalpy range of 0:8–2 = . Theoretical analysis has been used forndownstream of a backward-facing step using Gai’s nondimensional analysis. It has been found from the presentnstudy that approximately 10 and 8 step heights are required for the flow to reattach for 2 and 3 mm step heightnbackward-facing step models, respectively, at a nominal Mach number of 7.6.