Spreading of liquid to each tube and forming the thin film across surface area of the tube is the operating principle of falling film evaporator system. The falling film evaporator does have the advantage that the film is 'going with gravity' instead of against it. This results in a thinner, faster moving film and gives rise to an even shorter product contact time and a further improvement in the value of HTC. This type of evaporator is suitable for low fouling and low viscous fluid.
