Testing of a Falling-Film Evaporator for Adsorption Chillers

In this work, the performance of an innovative evaporator based on water falling film was investigated. The studied has been equipped with a recirculation system to maximise wetted surface. Tests have carried out in lab-scale adsorption unit connected test bench recently realised at Politecnico di Milano labs for evaluating heat transfer performances under realistic operating conditions. Several ad/desorption cooling cycles were performed, setting different liquid refrigerant initial contents (0.9–1.5 kg), chilled inlet temperatures (7–20 °C) and flow rates (200–1000 L/h) adsorbent bed (25–30 °C). Evaporation determined delivered capacity. Moreover, experimental data used calculate overall conductance (UA). Experiments showed how duty peaks are mainly due thermal level that enters evaporator, not content inside it because value only affects duration process. Instead, UA does depend temperature mass evaporator. is 540–570 W/K entering equal 10–20 °C, 0.9–1.5 kg.