Heat transfer in a liquid film on an unsteady stretching sheet

The heat transfer in a liquid film driven by a horizontal sheet is examined. The stretching rate and temperature of the sheet vary with time. The boundary layer equations for momentum and thermal energy are reduced to a set of ordinary differential equations by means of an exact similarity transformation. Numerical solutions of the resulting four-parameter problem are provided. It is observed that the variation of the sheet temperature with distance and with time has analogous effects both on the free surface temperature and the heat transfer rate (Nusselt number) at the sheet.