Numerical investigation of two-phase flow structure and heat transfer in a supersonic dusty gas flow over a blunt body

¹ LEMTA UMR CNRS 7563, ESSTIN Henri Poincare University Nancy, France
² Department of Materials Science and Engineering University of Virginia Charlottesville, USA
³ Faculty of Aerospace Engineering Baltic State Technical University St. Petersburg, Russia

Abstract

A dusty gas flow near the forward part of a blunt body is investigated numerically by an example of a crosswise supersonic flow over a cylinder. Considerable attention is paid to the fine flow structure and the temperature field of the carrier gas inside the boundary layer. Wide ranges of particle sizes and free stream particle volume fraction have been studied, and the possible interparticle collisions and two-way coupling effects have been taken into account. A combined computational fluid dynamics (CFD) / Monte Carlo method has been used for the computational simulation of the two-phase flow. The heat flux from the carrier gas and the energy flux from the particles to the body surface have been calculated. It has been found that the heat flux depends nonmonotonically on the particle size. The maximum heat flux has been observed for particles whose radius is just greater than the so-called critical particle radius, which is defined as the radius above which the particles reach the body surface and collide with it (particles with a radius below the critical one do not reach the surface). A physical explanation is proposed for this phenomenon which seems unexpected at first glance. The effects of the contact particle-wall heat transfer and the turbulence generation by particles are estimated.