PDF modelling and particle-turbulence interaction of turbulent spray flames

摘要: Turbulent spray flames can be found in many applications, such as Diesel engines, rocket engines and power plants. The practical applications are a motivation to investigate the physical phenomena occurring turbulent detail order able understand, predict optimise them. two-phase flow system consisting of reacting continuum phase dispersed liquid contained phase. In this thesis interaction between these two phases is being studied, specifically effects vaporisation presence droplets on turbulence characteristics (the two-way coupling effect). main goal research described develop evaluate stochastic Lagrangian models for that characterised by significant or dominant effects. first part thesis, isolated droplet studied several evaluated. problem briefly explained using some simple simulations general theoretical ideas concept group combustion introduced. second hybrid Lagrangian-Lagrangian method presented. transport equation joint mass density function (MDF) velocity composition, which solved indirectly Monte Carlo particle where Langevin type equations solved. This augmented finite volume mean Eulerian momentum, Reynolds stresses dissipation solved, making it approach solely MDF also method. A novel modification model pressure rate strain presented takes into account effect particles transfer. formulation then modified consistent with p ressure formulation. diffusion term implies Kolmogorov's hypothesis regarding structure function. An investigation scalar shows mixing affected vaporisation. Other developments extension Generalised Gradient Daly Harlow triple correlations an exact expression transfer dissipation. third results numerical test cases case Eulerian-Lagrangian was used influence investigated axially symmetric non-burning compared experimental data. Small improvements quantities over conventional noticed when used. case, flame performed illustrate performance complete proposed thesis. good agreement data controlled taking reduction drag coefficient heat due turned out crucial