Numerical study on turbulent two-phase flow in porous medium combustion chamber

To understand the working mechanism of the porous medium(PM)internal combustion engine,effects of a porous medium heat regenerator inserted into a combustion chamber on the turbulent flow char-acteristics and fuel-air mixture formation are studied by numerical simulation.The cylindrical chamber has a constant volume,in which a disk-shaped PM insert is fixed.A simplified model for the random structure of the PM is presented,in which the PM is represented by an assembly of a great number of randomly distributed solid units.To simulate flows in the PM a microscopic approach is employed,in which computations are performed on a pore-scale mesh and based on the standard k-ε turbulence model.A spray model,in which the effects of drop breakup,collision and coalescence are taken into account,is introduced to describe spray/wall interactions.Numerical computations are performed for the turbulent flows induced by a fuel spray outside and inside of the PM with different structure parameters.Calculation results show that the spray/PM interaction has substantial and positive influ-ences on the fuel-air mixture formation and homogenization in the combustion chamber,which could be very advantageous in engine applications.