Heat-transfer measurements with a catalytic flat plate in dissociated oxygen.

Heat-transfer measurements are presented which were obtained with catalytic and noncatalytic surfaces on a sharp flat plate. The experiments were made in a shock-tube flow of argon and dissociated oxygen, and are intended to provide a check on existing laminar boundary-layer theories. The design of the experiment is described, and the instrumentation and surface-conditioning requirements are discussed. Typical experimental data are presented to demonstrate the effects of shock-wave attenuation and other gasdynamic transients, and to show that these effects are negligible. The data obtained with the noncatalytic surface are compared with existing theories to demonstrate the importance of Prandtl number effects and variations in the p/j, product through the boundary layer. An approximate relation, based on an extension of Crocco's laminar boundary-layer theory, is given which accounts for these quantities and for surface recombination. It is found to be in good agreement with the data obtained with both the noncatalytic and the catalytic surfaces. The data obtained with both surfaces are used to infer the ambient atom concentration, as in diagnostic applications, and the inferred concentrations agree with those predicted using equilibrium theory with typical uncertainties of 5%.