Investigation of Plate Falling Film Absorber With Film-Inverting Configuration

The performance enhancement of absorbers is closely related to the investment costs of absorption cooling systems. In this paper, a new film-inverting design for plate falling film absorber is proposed. The absorber consists of consecutive inclined plates. The absorbent solution is distributed at the top of the first plate and forms a liquid film falling down along the plate. Meanwhile, the falling film absorbs the water vapor generated by the evaporator. At the bottom of this plate, the film is guided to the next one and at the same time the film is inverted and its inner side to the vapor is exposed. In this way, the absorption process can be enhanced. A mathematical model is developed for the simulation of heat and mass transfer in this new type of absorbers and is solved numerically. The experiments were carried out under different conditions and the influences of absorption pressure, solution flow rate, solution inlet temperature, and cooling water on the absorption process were investigated experimentally. Comparisons show a good consistency between the experiment and numerical results.