Problem of using the PIV-method for measurements in thin high-velocity shear layers

A PIV method is used to measure the flow velocity in a zone of interaction between a shock wave and a boundary layer on a plate in the case where the Mach number is $\mathrm{M}=1.43$. Two states of the incident boundary layer are considered (laminar and turbulent), and a boundary layer thickness can be two orders of magnitude smaller than the characteristic longitudinal scale of the flow. The results of measuring the velocity in the boundary layer, obtained using the PIV method at different settings of the equipment, and the results of measurements performed using various algorithms for determining the tracer particle displacement and reconstructing velocity fields from them. It is shown that the main constraint for increasing the spatial resolution is the tracer particle inertia.