Effects of temperature-dependent fluid properties on heat transfer due to an axisymmetric impinging gas jet normal to a flat surface

Heat transfer due to an axisymmetric laminar gas jet impinging onto a flat solid surface of uniform temperature is studied numerically, taking into account the temperature dependence of all fluid physical properties. Numerical solutions are obtained for the jet Reynolds numbers 200-2000, jet mouth-to-surface distances 1-4 times the jet nozzle diameter, and for helium-4, air, and carbon dioxide. Effects of the temperature dependence of the fluid properties are investigated using various kinds of reference temperatures and a viscosity correction method. A method of estimating the values of the local Nusselt number for temperature-dependent fluid from the constant-property solutions is proposed.