Flow Instability: Transition and Non Linearity
Presenting a Compressible 2D Linearized Hydrodynamic Stability Package: Modeling Surface Roughness via Modified Wall Boundary Conditions
9:18 am – 9:31 amMotivated by the study of transition to turbulence over rough walls, we present a computational approach that examines the effect of wall boundary conditions on hydrodynamic stability in compressible two-dimensional flows. First, we present an in-house linearized spatial and temporal analysis package, similar to existing solvers like LinStab2D and LASTRAC, that offers efficient adjustment of wall boundary conditions. Subsequently, we demonstrate our solver's promise by investigating modified boundary conditions, in conjunction with alternative baseflow configurations. The aim is to characterize the fidelity of a simplified representation of the roughness boundary condition and baseflow to embody the hydrodynamic stability of the boundary layer. This package emphasizes the opportunities and limitations of (smooth-wall) hydrodynamic stability when investigating roughness-induced instability, as compared to traditional direct numerical simulations that require geometrically resolved surface roughness and high computational cost.
Funding acknowledgement
This work has been supported under a NASA Space Technology Research Institute Award (ACCESS, grant number 80NSSC21K1117).
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