Shock tube spherical particle accelerating study for drag coefficient determination

Abstract.

An original particle accelerating technique has been developed for a shock tube. The trajectories of calibrated spherical particles $2\;{\mathrm{mm}} (\rho _p=1170\;{\mathrm{kg/m^3}})$ and $0.3\;{\mathrm{mm}} (\rho _p=500\;{\mathrm{kg/m^3}})$ in diameter have been measured by the multiple exposure shadowgraph technique coupled with a high speed drum camera. Both particle velocity and acceleration, deduced from the experimental trajectories, allow the determination of the drag coefficients for different, subsonic and supersonic, flow regimes for the particle Reynolds numbers from $5\cdot 10^2$ to $5\cdot10^4$ and the particle Mach numbers from 0.6 to 1.2. The drag coefficient values have been compared with different correlations found in the literature.