Film cooling effectiveness in a particle-laden flow

A computational method is developed to evaluate the cooling effectiveness of a tangential slot in a particle-laden flow. The physical problem analyzed involves the tangential injection of a coolant at a wall subjected to convective heating from a turbulent boundary layer and radiative heating from hot particles. Previous published analyses did not include radiative or particle effects. The boundary-layer equations, including energy and species conservation, are solved using a finite difference scheme. The particle transport equation is also solved by a finite difference technique. A two-dimensional formulation for the solution of the radiative equation of transfer is developed using the spherical harmonics method. This formulation is different from those previously published in that it solves for an azimuthally integrated form of the intensity. This approach reduces the number of unknowns in the solution and is therefore more computationally efficient. Particle optical properties are obtained using the Mie scattering theory. A parametric study is performed to determine the effects of wall emissivity and other parameters on cooling effectiveness and particle deposition on the wall.