NUMERICAL STUDY OF THE EVAPORATION OF A FALLING OSTWALDIAN FILM ALONG AN INCLINED FLAT PLATE INTO A LAMINAR STREAM OF HUMID AIR

The present paper deals with the evaporation of a falling Ostwaldian film along an inclined isothermal plate into a laminar stream of humid air. The governing boundarylayer and the matching conditions are solved using a finitedifference method. Four liquids are considered : two pseudoplastic, and the other two dilatant. The effect of the air flow conditions, the inclination and the temperature of the plate, as well as the inlet temperature of the film on the evaporation rate and the thickness were studied. A comparative analysis between one dimensional, partial two-dimensional and full two-dimensional approches is made. It was found that the inertia terms cannot be neglected in the momentum equation of the liquid film, and these differences increase as the flow behaviour index increases.

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