Studies On The Behaviour Of Solid Particles In Turbulent Gas Flows

This thesis describes a study on the behaviour of small solid particles in a numerically simulated turbulent flow. The numerical simulation of the pseudo-turbulence was based upon a vortex method in which the velocity fluctuations of the turbulent flow were simulated by arrays of randomly positioned vortices. The calculation of the motion of the spherical particles was based upon the forces acting upon a particle as a function of the local fluid velocity.;The motion of the solid particles in both a free turbulent flow and a pipe flow were studied. The simulations developed for free turbulence and particle motions were tested and it was demonstrated that Lagrangian particle velocity signals could be generated and analysed. This analysis enabled the Lagrangian motion of a solid particle to be determined from Eulerian turbulent velocity traces.;An experimental study was performed to measure turbulent fluid velocity signals in a fully developed two-phase liquid-solids pipe flow for mass solids loadings between 0 and 10%. A simulation for the coherent flow structures in the turbulent shear flow adjacent to a wall was also investigated.;Finally, these studies showed that it was possible to simulate the behaviour of small solid particles in numerically generated flow fields and obtain realistic descriptions of particle motions