Development of a Mathematical Model for Heat Transfer of Moving Fluids in a Plane-Parallel Heater

This paper describes the developed approximate analytical method for solving the problem of heat transfer in a plane combined channel consisting of heated and unheated parts. According to the presented method, the problem of finding a solution to a partial differential equation with respect to a temperature function is reduced to integrating an ordinary differential equation with respect to a new unknown function - the heat flow density on the surface of the area under study. The authors obtained an approximate analytical solution of the problem, which gives an error of no more than 4% in the first approximation, compared to the numerical solution of this problem. The graphs of the temperature distribution in the first and second parts of the plane channel are constructed and analyzed. This method can be used by specialists operating the heating devices with a heat source to determine the heat flow density, when it is not possible to determine the heat flow through independent measurements using sensors (calorimeters).