Decomposition of teflon heat protective coatings at hypersonic flight velocities

Abstract

We consider the decomposition of a teflon thermal protective coating along the generatrix of a blunted solid of revolution for various Mach numbers and pressures of the incident flow. On the basis of preliminary parametric study of the equations of a laminar boundary layer with pressure gradient, calculation of the teflon decomposition parameters is reduced to solution of a system of nonlinear and transcendental equations. It is shown that the temperature distribution and decomposition rate along the generatrix of the solid of revolution have a monotonie character, and that the effective enthalpy of the material remains constant along the body. A simple approximate formula is proposed for calculation of the teflon decomposition rate.