Study On New Dry-type Technical Air Conditioning System

To integrate the air-cleaning effect of the silica gel rotor and the high-efficiencyheat collect and transfer effect of high-temperature heat pump, the aim of this researchis to develop air-source high-temperature heat pump, which can provide higherair-cooled condensation temperature. Thus, self-regenerating desiccant wheelcombined with high-temperature heat pump air-conditioning system is brought up.The high-temperature heat pump provides energy for the desiccant wheel’sregeneration, effectively the energy sources and quality are solved, at the same timefulfills the air-conditioning cooling load. Within the system, the balance of heat andcold and self-regeneration are achieved, which can largely save energy. This studyprovides scientific evidences for the promotion of the dehumidifying air-conditioningsystems.The research of heat pump includes the selection of working fluid, optimizationof the components and performance test. Through calculation and comparison basedon properties, R142b is considered the most suitable working fluid when working inhigh-temperature range. The optimization of the system is based on the selection ofthe capillary and increasing heat-exchange surface of the condenser. In virtue ofsimulating air states, the operation parameters and performance of the system istestified on standard air-enthalpy test unit. The final test shows that while the inlet airof evaporator is in a states of simulating the air after dehumidifying (the temperatureis40℃、45℃、50℃respectively), the condenser exit air temperature is up to79.96℃,which is sufficient to the requirement of the regeneration of the desiccant. Theconpression ratio is between4.5and5.5. The experiments testified the suitability ofthe high-temperature heat pump in the combined system.According to the silica gel wheel’s adsorption of water vapor, a one-dimensionmathematical model of heat and water vapor’s mass transfer is established. So docomponent model and whole-machine model. Calculating programs are made withMATLAB, for the sake of simulating the operating parameters and energyconsumption. The results of the simulation agree well with the experimental results,and in high accuracy. Through analysis and model calculation, the operatingparameters and performance of the system according to the changing indoor andoutdoor air state can be gotten easily. Compared with conventional reheat system, thiscombined system has the advantage of controlling temperature and humidity separately besides its air-cleaning effect. Thus it has obvious energy-saving effect, upto35.1%under normal condition, and EER rises by38.1%. As the increase of the wetload, the energy-saving effect will be further increased.