Development of an Eulerian Polydisperse Multiphase Flow Model

The effects of polydisperse particle size distributions on the physics of compressible multiphase systems, such as volcanic eruptions and metalized blasts, can have a significant impact on the particle dynamics. For example, in dust explosion scenarios, the smaller particles closely follow the flow and ignite and burn quickly. Larger particles in the size distribution have much longer ignition and burning time scales, which substantially increases the duration of the explosion. Most Eulerian multiphase models do not account for realistic particle size distributions. To overcome these limitations, a polydisperse Eulerian multiphase flow model was developed based on quadrature-based moment methods. The transport equations that couple a compressible gas to a polydisperse mixture of particles was derived using kinetic theory. The gas-polydisperse multiphase model accounts for particle collisions, drag, convective heat transfer, compaction waves, etc. Ongoing work includes using more accurate numerical flux schemes, such as HLLC and AUSM+-up, and adding chemical reactions to simulate dust explosion scenarios.