| In recent years,the tightness of buildings near-zero-energy buildings has been continuously enhanced,causing the problem of indoor air quality degradation.Therefore,it is necessary to introduce fresh air that meets the air quality requirements from the outside,and the outdoor ar temperature in the severe cold regions is much low,which increases the fresh air load of the building.In summary,this study has studied a heat recovery dedicated outdoor air unit that can be applied to severe cold regions with high energy efficiency ratio,and aims to provide outdoor air that meet the thermal comfort requirements of buildings under the premise of energy saving.Based on the climate parameters of Harbin,this paper studies the system design,operation performance,energy consumption and energy conservation of the independent heat recovery fresh air unit studied by combining theoretical analysis,experimental analysis and simulation calculation.Firstly,this paper combines the existing technology to theoretically analyze the system selection,structural design,refrigerant selection and heat pump system of the new wind turbine.And according to the climate characteristics of the severe cold region,the new air and return air full heat recovery and R410 A quasi-secondary compressed air source heat pump are finally selected.The air source heat pump combines the system form and calculates and verifies the heat pump system.After that,according to the design scheme,the prototype was produced and the running experiments were carried out with the set air supply temperature of 16 °C,20 °C and 24 °C respectively.The effects,performance,heat recovery efficiency and energy consumption of the new fan in the cold region were studied..Finally,in order to make up for the sub-site experiment,it is difficult to traverse the limits of all outdoor air temperatures.According to the air-source heat pump with the compressor model of this unit,the performance parameters obtained during the heating season at an outdoor temperature of-27.5 ° C ~-10 ° C are passed.The condensing pressure was corrected,and the curve of the energy efficiency ratio COP of the new fan was changed with the outdoor temperature.The experimental results were brought into the verification of the rationality.Finally,the new wind turbine was obtained in a typical severe cold area.The total heating capacity,total energy consumption,and seasonal energy coefficient HSPF of the climate-characteristic heating season are compared and compared with the primary energy utilization and energy consumption of the two traditional fresh air systems.The field experiment and simulation calculation of the outdoor air unit in the cold region show that the air source heat pump heat recovery independent fresh air unit can operate normally under the premise of ensuring fresh air volume and supply air temperature;heat pump system works well during operation and the exhaust gas temperature is low.Bdesides,it shows that the operating COP is at a high level,which can be guaranteed to be around 3.5,and higher than 4.0 at higher temperatures;the heat recovery efficiency during operation can be stabilized at about 55% in a high outdoor temperature environment;a reasonable set supply air temperature is 20 °C.In the heating season,the heating seasonal performance factor of the outdoor air unit is 2.68,and the power consumption per unit volume of fresh air is 3.32 Wh/m3,which is about 1/2 and 2/3 less than the energy consumption of fresh air per unit volume of the two traditional fresh air systems respectively.And the primary energy utilization rate is 1.300,which is twice and three times of the two traditional heat recovery fresh air systems. |
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