Inception length to a fully developed, fin-generated, shock-wave, boundary-layer interaction

Abstract

An experimental study of fin-generated, shock-wave, turbulent, boundary-layer interactions confirmed previous observations that, sufficiently far from the fin apex, such interactions become conical. For Mach numbers from 2.5 to 4 and fin angles from 4 to 22 deg, the inception length to conical symmetry was found to increase weakly with Mach number. Also, the inception length was found to depend primarily on the inviscid shock angle, this angle ranging from 21 to 40 deg. The inception length decreased with shock strength and was small (approximately constant at three boundary-layer thicknesses in length) at the largest shock strengths encountered.

Fluctuating wall pressures near separation in highly swept turbulent interactions

“…As the strength of the interaction increased, the VCO approached the fin leading edge. This phenomenon had been observed in the previous work of Lu and Settles 16 at lower Mach numbers. Overall, the agreement between the surface features of the present and earlier investigations indicates that the experimental flowfield for the current study was effectively semi-infinite and free of irregularities.…”

“…Estimates of the VCO location were made using the data of Ref. 16, and the radial distance to the transducers from the VCO, /? vco , was determined for each study.…”

3-D Inlet Shock-Boundary Layer Interactions - PIV Database for the Second SBLI Workshop

“…Incident oblique shocks, compression corners, swept fins and normal shocks generate pressure rises in the boundary layer that result in thickening or separation of the boundary layer [4][5][6][7][8][9][10][11][12][13][14]. Unfortunately, these flows are sufficiently different in structure that each display characteristic scales impeding global parameterization based on two-dimensional analyses and a developed understanding of shock-foot unsteadiness is still a matter of some concern.…”

“…single, frequently small, region of interest). The test apparatus incorporates many critical features of real non-axisymmetric high speed inlets including shock boundary layer interactions (SBLI) on the side walls (Swept-Shock and/or Fin-Plate), the bottom wall(an Oblique Impinging Shock), and in the corner formed by the interaction of the bottom and side walls, as well as other geometries [4][5][6][7][8][9][10][11][12][13][14]. To the authors' knowledge (see section B.4), this is the first such dataset of it's kind.…”