Correction Method for Particle Velocimetry Data Based on the Stokes Drag Law

A correction method based on the Stokes drag law was developed for flow velocimetry using tracer particles. The present method can be used to calculate the corrected velocity from the measured velocity and its spatial gradient without the need to solve the whole flowfield. Velocity measurement was conducted for sonic transverse injection into Mach 1.8 flow using particle image velocimetry. The correction method was applied to the velocity field obtained from the particle image velocimetry data. The corrected data showed the positions and shapes of the shock waves in the measurement region more clearly. The corrected peak velocity downstream of the shock waves became closer to the theoretical values. The jet streamlines calculated from the corrected and original particle image velocimetry data were compared. The streamlines from the corrected data went lower than those from the original data.