Unsteady Heat Transfer and Fluid Flow in Porous Combustion Chamber Deposits

A computational investigation of unsteady heat transfer and fluid flow in a porous combustion chamber deposit has been performed. The inside surface is exposed to an ideal gas with large fluctuations in temperature and pressure, while the outside surface is taken to be in perfect contact with a thick, aluminum wall.

The nonlinear, partial differential equations describing the transport of mass and energy, and Darcy's law were solved simultaneously using a finite-difference technique. Experimental surface temperature and pressure measurements were used as boundary conditions, local thermodynamic equilibrium between the gas and solid has been assumed to exist.

A parametric study has been performed to determine the effects of deposit porosity and permeability on the mass flow in the deposit, surface heat transfer, and heat transfer to the coolant. Conduction transport of energy was found to dominate the convective transport.