The 2D Flow Around Tilted Plate

The 2D problem on stratified flow around a strip is studied numerically and experimentally on the basis of the system of fundamental equations of incompressible viscous fluid mechanics taking into account diffusion effects and neglecting heat transfer. Strongly and weakly stratified fluid flows are considered, as well as potentially and actually homogeneous ones when the buoyancy effects, respectively, are assumed extremely weak or even neglected completely. Initial condition is the diffusion-induced flow on a motionless obstacle, which occurs as a result of interrupting the molecular flux of a stratifying agent on the plate surface. Influence of a set of problem parameters on the flow structure and dynamics is studied, including longitudinal and transverse dimensions of the plate, its shape, angle of attack, and velocity of movement. Analysis of the results shows that the unsteady problem does not have a stationary limit over the entire range of flow parameters due to its internal multiscale structure. The calculated field patterns, being specific for the basic physical variables and their gradients, are in a qualitative agreement with the laboratory data. In the extreme cases, the results converge to the well-known solutions, in particular, to the Blasius solution for the half-plane set in the direction of free stream

The work is supported by the Russian Foundation for Basic Research (project RFBR 18-05-00870), the experiments have been carried out at the stand of the LMP of the URS "HFC IPMech RAS" by project AAAA-A17-117121120015-8

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