The shock-induced dispersal of particle curtains with varying material density

We present results from experiments within Sandia National Labs’ multiphase shock tube on the shock-induced dispersal of dense particle curtains. The curtain spread rate was measured by tracking the position of the upstream and downstream fronts using high-speed schlieren images. The effect of particle density on the curtain spread rate was examined by comparing curtains comprised of soda lime, stainless steel, and tungsten particles at volume fractions φp=9% and φp≈20%. Various incident shock strengths were investigated, with shock Mach numbers ranging from 1.4 to 1.7. Non-dimensionalized time scales of the spreading process were generated using two scaling methods from literature; one related to the pressure ratio across a reflected shock and the other to the incompressible drag through a grid. Both scaling methods successfully collapse the spread rate of curtains with different particle densities, while only the drag-based scaling properly accounts for variation in volume fraction. A new scaling based on a simple force balance and the experimentally measured pressure differential across the curtain achieves the tightest collapse of all methods tested. Correlations are introduced for the pressure upstream and downstream of the curtain which incorporate the effect of volume fraction and successfully collapse the curtain spread rate when used with the simple force balance scaling. These results expand the parameter space over which the examined scaling methods are valid and introduce correlations that accurately estimate the pressure behind the transmitted and reflected shocks. •Measured the effect of volume fraction, incident shock strength, and particle density on the particle curtain spread rate.•The drag-based scaling of DeMauro et al. collapses the spread rate of curtain with different density and volume fraction.•The pressure ratio-based scaling of Theofanous et al. accounts for particle density, but not volume fraction.•Introduced a new scaling based on a simplified force balance that produced the best collapse of any scaling tested.•Developed new correlations to estimate the upstream and downstream curtain pressures.