APPLIED HORIZONTAL ROUND TUBE BANKS FALLING-FILM ABSORBER FOR ABSORPTION REFRIGERATION SYSTEM FOR MAKING ICE

Abstract

Aiming to develop the application of NH₃-H₂O absorption refrigeration system in Vietnam, one of the key research directions is the selection of absorber structure which is expected to be fabricated in Vietnam without demand of new infrastructure investment. After the heat and mass transfers occurring between liquid and vapor in falling film absorber had been studied theoretically and experimentally, we further clarified its suitability when applying this type of absorber in Un-intermittent absorption refrigeration system for making ice. A series of experiments varying the concentration from 29.5% to 32.5% was done to look for the suitable intake concentration. The results showed that the suitable intake concentration is 31% which corresponds to the following properties: the coefficient of performance COP = 0.436, the brine refrigeration performance COP_u = 0.262, the average temperature of ammonia vapor leaving the generator is t₅ = 116.5°C, the average concentrations of weak and strong solution are 29.14% and 34.11%, respectively.