Dehumidifying Wheel And Heat Pipe Heat Exchanger Compound Air Conditioning System

Rotary wheel dehumidification and the advantage of the utilization of renewable energy are widely used in industrial sites with higher requirements for humidity,which are gradually valued in civil architecture.The new rotary dehumidification air conditioner can decrease the energy consumption of the system.Using the air-conditioning system of gravity heat pipe heat exchanger with deep dehumidification performance,the traditional heat exchange device can be replaced.A combined air-conditioning system with rotary wheel dehumidification and heat pipe heat exchanger is put forward.With the method of theoretical analysis,numerical simulation and experiment,the heat transfer performance of gravity heat pipe heat exchanger is studied.On the basis of it,the research on the performance of the combined air-conditioning system with two stage rotary wheel dehumidification and heat pipe heat exchanger and the usability of the system in different regions is performed.The heat and mass transfer model of gravity heat pipe heat exchanger is established,the effects of the air state parameters and structural parameters of heat pipe heat exchanger on the heat transfer efficiency of gravity heat pipe heat exchanger are studied.The results suggest that when the gravity heat pipe heat exchanger has better temperature uniformity when it operates,The temperature difference between the evaporation side and condensation side of a single heat pipe is within 0.5?.The air velocity on the both sides of the heat exchanger increases from 0.5m/s to 2.5m/s.The efficiency of the heat exchanger reduces by 12%,which is lowest when the flow ratio of both sides of the heat exchanger is 1.The efficiency of the heat exchanger can be enhanced by changing the air flow ratio on both sides.The fin spacing of the heat exchanger increases from 2.1mm to 4.1mm,and the efficiency of the heat exchanger reduces by 10%,which ranges from 0.62 to 0.90.The experimental platform of the combined air-conditioning system of rotary wheel dehumidification and gravity heat pipe heat exchanger is set up.The research on the performance of the system and its components is carried out through experiment.Experimental results suggest that the dehumidification capacity of the rotary wheel dehumidifier is mainly affected by the temperature of treated air,moisture content of regeneration air and regeneration temperature.The dehumidification capacity of the rotary wheel dehumidifier can decrease by 50%or so when the temperature of the treated air(23?-31?)and the moisture content of the regenerated air(5.6-9.6g/kg)are changed.When the temperature of the regenerated air changes from 60? to 110?,the dehumidification capacity of the rotary wheel dehumidifier increases by 82%or so.The efficiency of the gravity heat pipe heat exchanger is mainly affected by the temperature of both sides of the heat exchanger.Through experimental examination,the efficiency of the heat exchanger can be increased to 8%when the temperature of the treated air increases from 23?to 31?.When the temperature of the regenerated air changes from 60? to 110?,the efficiency of the heat exchanger increases by 14%approximately.When the air velocity increases from 0.5m/s to 2.5m/s,the efficiency of the heat exchanger decreases by 9%.The increase in air velocity is conducive to the combined air-conditioning system of rotary wheel dehumidification and heat pipe heat exchanger.The experimental measurement suggests that when the wind velocity increases,the cooling capacity can be increased by 111%,and the thermal performance coefficient of the system can be increased by 167.5%.The thermodynamic analysis of the combined air-conditioning system of the rotary wheel dehumidification and heat pipe heat exchanger suggests that the main exergy loss of the system is the drying wheel and electric heater.For the exergy loss of the sensible heat exchanger accounts for a large proportion and the sensible heat exchanger with high efficiency can be used to optimize the system.On the condition of meeting the requirement of the same dehumidification capacity,in comparison with the combined air-conditioning system of one stage rotary wheel dehumidification and heat pipe heat exchanger,when the regeneration temperature of a single dehumidification rotary wheel is 80? in the combined air-conditioning system of two stage rotary wheel dehumidification and heat pipe heat exchanger,the requirements can be satisfied.And the regeneration energy consumption only accounts for 43%of the regeneration energy consumption of dry rotary wheel of the dehumidification system.The performance coefficient of the two stage dehumidification air conditioning system is 13.3%higher than that of one stage system.The effect of the air state parameters on the combined air-conditioning system of the two stage rotary wheel dehumidification and heat pipe heat exchanger is studied by solving the three-dimensional mathematical model.The results suggest that the higher the inlet temperature of treated air is,the better the cooling performance of the system is,the lower the temperature of treated air,the better the dehumidification performance of the system is.When the lowest inlet temperature of treated air is 28?,the dehumidification capacity of the system is largest.The difference between the inlet moisture content and outlet moisture content of the treated air is 14.1?.When the largest humidity of treated air is 25.2g/kg,the dehumidification capacity of the system is largest.The difference between the inlet moisture content and outlet moisture content of treated air is 14.2g/kg.The combined air-conditioning system of rotary wheel dehumidification and heat pipe heat exchanger has apparent advantages on high humidity occasion.The error between the simulation results of the built system through TRNSYS simulation and the experimental results is within the 15%.When the solar energy is added to the dehumidification air-conditioning system,the regeneration energy consumption of electric heating can be reduced.And the energy efficiency of the system is higher.In high humidity areas,the performance coefficient of the system can reach 0.45,The combined air-conditioning system of rotary wheel dehumidification and heat pipe heat exchanger can meet the requirement of air treatment.