Investigation of the Influence of Constant Adverse Pressure Gradients on LaminarBoundary-Layer Stability at Mach Number 8

摘要

Measurements of fluctuating-flow and mean-flow parameters were made in theboundary layer on each of two axisymmetric, constant pressure gradient bodies in an investigation of the influence of adverse pressure gradients on the stability of a laminar boundary layer in hypersonic flow. Each test article was slender, constant pressure gradient flare combined with a sharp cone forebody with a 7-deg half angle. The test articles differed in the magnitude of the pressure gradient. The flow-fluctuation measurements were made using constant-current hot-wire anemometry techniques. Boundary-layer profiles and model surface conditions were measured to supplement the hot-wire data. Testing was done at Mach number 8 with a free-stream unit Reynolds number of 1.0-million per foot. The test equipment, test techniques, and the data acquisition and reduction procedures are described. The test was the ninth in a series of efforts which have investigated various aspects of hypersonic boundary-layer stability. Keywords: Conical bodies; Laminar flow; Boundary layer flow; Hypersonic flow; Wind tunnel tests; Boundary layer stability. (EDC)