(290d) Falling Film Evaporation - Interaction of Heat and Mass Transport

Vaporization of liquids can be efficiently achieved by flowing the liquid as a falling film on vertical or inclined heat transfer surfaces.   Such evaporators are particularly useful for applications where fluids are temperature sensitive, minimal pressure drop is necessary, and short residence time is desired.  Engineering design of falling film evaporators have traditionally relied upon heuristic experience and empirical correlations.   Recent research has significantly improved mechanistic understanding of several key phenomena; leading to corresponding improvements in design methods. This paper discusses one of the key phenomena – the interaction of simultaneous mass transfer and heat transfer in the falling films.