Calculating transient wall heat flux from measurements of surface temperature

Wall heat fluxes can be derived from time resolved measurements of the surface temperature. This paper describes an analytical approach to calculate the heat flux from an analytical solution of the one-dimensional transient energy equation with transient boundary conditions using the Laplace transformation. The results are compared to simple test cases for which the heat fluxes are given in literature. The method is used to calculate the heat flux from a fuel spray to a wall at diesel engine conditions.