Heat transfer dynamics associated with the simultaneous growth of solid-liquid melt layers

摘要

A computational model is developed to study the effects of alumina layer formation on an ablative surface, when exposed to high temperature particle laden gas flow. The one-dimensional model is developed taking into consideration the thermal loading, particle loading and the temperature dependence of the thermo-physical properties of alumina. A fully implicit finite volume method is used to solve the coupled set of non-linear heat conduction equations. The solidification interface is tracked using the Lagrangian interpolation technique. The particle mass flux was found to be the major factor affecting the solid layer growth rate and the heat transferred to the ablative layer. The gas heat flux also has a major effect on the solid growth rate and the heat transferred to the ablative surface, but only for the lower particle mass fluxes. On the other hand the particle temperature has a linear effect on the solidification dynamics and the heat transferred to the ablative surface for all particle mass fluxes. The heat transferred to the ablative surface is reduced by approximately 40-90%, depending on the mass fluxes, due to the formation of the alumina layer.