The effect of three-dimensional deformations on local heat transfer to a nonuniformly heated falling film of liquid

An experimental investigation is performed of heat transfer under conditions of flow of a water film on a vertical surface with a heater $150\times150$ mm in size in the range of the Reynolds number values from $1$ to $45$. A map of modes of flow of the liquid film is plotted, and regions of heat transfer are identified. Data are obtained on the longitudinal coordinate dependence of the heater wall temperature and of the local heat flux on the symmetry axis of the heater. Local coefficients of heat transfer are measured. The experimental data are compared with the results of numerical calculations for a smooth film. The effect of the forming of jet flows on heat transfer to the liquid film is analyzed.