Prediction Techniques for Three-Dimensional Shock-Wave/Turbulent Boundary-Layer Interactions

Abstract

The design of efficient flight vehicles for sustained operation at high Mach numbers requires the understanding of the aerodynamic heating generated in interfering flowfields. The three-dimensional shockwave/turbulent boundary-layer interaction is typical of such flowfields and is one that produces severe localized heating. The Air Force Flight Dynamics Laboratory has conducted an extensive experimental investigation into such interactions. This investigation began with a simple fin/flat-plate model through which a substantial data base was obtained for Mach numbers of 3 to 6 and Reynolds numbers of 1.5x 106 to 28.0 x 106/ft. The study then was extended to a fin/ogive-cylinder model. This paper presents the correlation of peak aerodynamic heating in the interaction region as derived from the fin/plate model and the methods by which the correlation is applied to the missile configuration at arbitrary pitch and roll attitudes. This paper also documents the observed effects of boundary-laye r tripping on peak heating levels. It was found that the process of tripping significantly reduces the peak heating magnitude. The implications of this on experimental and vehicle design are yet to be explored. Nomenclature M = Mach number np = exponent in peak pressure correlation nst = coefficient in peak heating correlation P = pressure St = Stanton number X = distance in direction of freestream Y = distance normal to freestream Z = distance normal to model surface aF = fin deflection angle aM - missile model angle of attack /? = missile fin roll angle d = boundary-layer thickness at fin apex 6 = fin shock-wave angle = angle to the peak heating location \l/ = inviscid streamline turning angle Subscripts