The effect of polydispersity on dust lifting behind shock waves

Knowledge-based modeling of dust lifting behind shock waves is a prerequisite for realistic simulation of dust explosions. Mostly numerical simulations of this process focus on dusts consisting of monodisperse particles, while real dusts are polydisperse. This article investigates the effect on the lifting process of the dust being polydisperse with a log–normal distribution of particle sizes. The spatial distribution of the various sizes in the rising layer is studied, and statistical results for the rise, the collision frequency and the particle kinetic energy are compared for polydisperse and monodisperse dusts. It is shown that a layer consisting of polydisperse particles rises significantly faster than a one consisting of monodisperse particles, all other parameters being the same.

Knowledge-based modeling of dust lifting behind shock waves is a pre-requisite for realistic simulation of dust explosions. Mostly numerical simulations of this process focus on dusts consisting of monodisperse particles, while real dusts are polydisperse. This article investigates the effect on the lifting process of the dust being polydisperse. The spatial distribution of the various sizes in the rising layer is studied and results are compared for polydisperse and monodisperse dusts. A layer polydisperse particles rises significantly faster than a one consisting of monodisperse particles, all other parameters being the same.The figure shows an example of the distribution of heights of the particles as a function of their size during the process of lifting of the layer behind a passing shockwaveFigure optionsDownload as PowerPoint slide