Boundary Layer Analysis of Shock Tube Flows

Andrea Fagnani; Olivier Chazot; Brett A Cruden

NASA NTRS · 20260003831

Boundary Layer Analysis of Shock Tube Flows

Andrea Fagnani·Olivier Chazot·Brett A Cruden

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Abstract

Shock tubes offer a controlled environment to reproduce kinetic and radiative phenomena characteristic of atmospheric entry flows under ground-test conditions. The boundary layer developing behind the incident shock wave determines the available test time, influences particle residence times important for similarity scaling, and can affect radiative energy transport. In this study, we couple a quasi-1D space marcher with the compressible boundary-layer equations to numerically compute the post-shock flow in a shock frame of reference for various test gas mixtures representative of different planetary atmospheres. The solvers are individually verified against CFD simulations and analytical correlations available in the literature. Coupled solutions are computed for a finite-rate chemistry in the boundary layer and a non-catalytic isothermal wall. Results yield refined estimates of the maximum separation distance, as well as insights into concentration profiles of relevant species within the boundary layer.

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Andrea Fagnani, Olivier Chazot, Brett A Cruden. Boundary Layer Analysis of Shock Tube Flows. https://ntrs.nasa.gov/citations/20260003831

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