INSTABILITY OF RADIATION-INDUCED FLOW IN AN INCLINED SLOT

Abstract

The instability of radiation-induced flow of a participating fluid in an inclined slender slot irradiated from one boundary is studied numerically for the inclination from 0-degrees to 90-degrees. The Eddington approximation is employed for the equation of transfer, and the pseudospectral method is used to solve the linearized perturbed equations. At an angle smaller than the transition angle the instability sets in as stationary longitudinal rolls. At an angle greater than the transition angle the instability occurs in the form of travelling transverse waves. The transition angle for the fluid of Pr = 0.71 is found to be minimum at the optical thickness near unity. Increasing optical thickness decreases the penetration of radiant energy, consequently increases the stability. The critical Rayleigh number increases rapidly with increasing the optical thickness as the optical thickness is greater than one.