A new formulation of a spray dispersion model for particle/droplet-laden flows subjected to shock waves. (25th December 2020)

• Record Type: Journal Article
• Authors: Gai, G.; Thomine, O.; Kudriakov, S.; Hadjadj, A.
• Is Part Of: Journal of fluid mechanics. Volume 905(2020)
• Publication Date: 2020-12-25
• Subjects: gas dynamics, -- shock waves, -- particle/fluid flow; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2020.748
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract: Abstract : A new analytical model is derived based on physical concepts and conservation laws, in order to evaluate the post-shock gas velocity, the gas density and the spray dispersion topology during the interaction of a shock wave and a water spray in a one-dimensional configuration. The model is validated against numerical simulations over a wide range of incident Mach numbers $M_s$ and particle volume fractions $\tau _{v, 0}$ . Two regimes of shock reflection have been identified depending on $M_s$, where the reflected pressure expansion propagates either opposite to the incident shock-wave direction for weak incident Mach numbers or along with it for strong Mach numbers. The numerical simulations reveal the presence of a particle number-density peak for $M_s > 2$ and with particle diameters of the order of ${O}(10)\ \mathrm {\mu } \textrm {m}$ . The formation of the number-density peak is discussed and a necessary condition for its existence is proposed for the first time.