Structural Study And Ice-Making Characteristics Analysis Of Multi-Generator In Adsorption System

This study is from a docking project of Wuhan Science and Technology, named solarcollector type absorption refrigeration system drive by low pressure steam. Adsorptionrefrigeration technology can use low-grade heat energy as driven energy, such as solarengine exhaust, low pressure steam and low pressure steam and so on; and use friendlysubstances to the atmospheric environment like water, methanol and ammonia as arefrigerant. What’s more, adsorption refrigeration systems can be used to strong shockplaces with no moving parts. So, domestic and foreign scholars have done extensiveattention and in-depth study. However, it has not yet been widely used for main reasons toocomplex systems, small amount of cooling and low efficiency.The heat and mass transfer of adsorbent bed, which is a key component in theadsorption refrigeration system, directly affect the performance of the system. To achieve acontinuous output, multi-generator absorption refrigeration system is used in this study onthe base of analyzing the research situation. In ice conditions,140℃low-pressure steamheat as driving energy and calcium chloride-ammonia as a refrigerant for adsorptionrefrigeration working pairs, the heat transfer characteristics of adsorbent bed is studied.Firstly, the structure of shell and tube adsorption bed is determined initially, accordingto the adsorbent material parameters and system operating requirements. By analyzing thethermal resistance of heat pipes and the of adsorption bed, it theoretically studied the systemperformance influence of the sensible heat and how to reduce the switching transition timeto overcome the sensible heat. The results show that the system cooling efficiency COP is27%, and the cooling capacity per mass adsorbent is172W/kg. Secondly, to improve systemperformance, it’s added external fins outside the unit tubes. The result is only5%increase.Finally, in order to reduce the volume and improve the coolingefficiency, the spiral plateadsorption bed is studied in theory. In case of same cooling capacity and filled adsorbent. The size of the adsorbent bed is smaller43%and the cooling efficiency improves5.3%tothe shell and tube bed. The study has provided a theoretical basis for the adsorptionrefrigeration technology industry.