Two-fluid flows of a mixture of gas and solid particles with 'sheets' and 'filaments' arising in flow past nonporous surfaces

The two-fluid model with dispersed phase (a continuous medium without internal pressure) is used to investigate the appearance of sheets and filaments in the flow of a gas-particle mixture past nonporous surfaces. Equations and conditions are derived for the motion of sheets and filaments and the shedding of these formations from surfaces. It is shown that a shed (free) sheet collects particles, separating the regions of mixture and pure gas and filtering the mixture as it were. Cases of nozzle flow in which a detached sheet is reattached to the wall are examined. It is demonstrated that a sheet can form during rarefaction in the supersonic flow of a two-phase mixture past a discontinuity.