MODELING OF LAMINAR PHENOMENA OF CHEMICAL HEAT-TREATING PROCESSES

A general equation of the concentration distribution under laminar conditions was proposed. On the basis of this equation an integral method was derived. This method is based on setting a balance of flux gradients of the transfer phenomena that occur. It was shown that the flux gradient is identical to the characteristic quantity N which defines the state at the cross-section perpendicular to the surface, the definition of which enables the formulation of the proposed general equation. The general approximative integral method was applied to the phenomena on the metal surface, mass transfer during a heterogeneous chemical reaction in the laminar boundary layer over a flat plate-measuring foil. A model of the mass transfer coefficient was presented as a function of the limiting heterogeneous chemical reaction rate constant, characteristic time relation and surface function of the appropriate gas atomosphere. The proposed model is a theoretical basis for the development of a measuring device of non-equilibrium gas carburizing processes.