| Based on the climate characteristics of Nanjing,this paper studied a multi-function air source heat pump hot water unit Based on the common air source heat pump,the unit added a hot water tank to make the unit realize refrigeration,refrigeration and hot water,heating and heating and hot water and other operating modes.The multifunctional air source heat pump solves the problem that the ordinary air source heat pump unit can not provide domestic hot water during heating(refrigeration)during the whole year of operation,and recovers the condensed waste heat to obtain free hot water,which plays the role of water cooling condensation.It makes the unit run more efficiently under high temperature conditions in summer.In this paper,the multi-function air source heat pump hot water unit is taken as the research object,and the reasonable experimental scheme of the unit test bench is developed.The data results are obtained through experiments,and the air source heat pump hot water preparation unit is operated in the Nanjing area according to the experimental results.The characteristics and factors affecting the operation of the unit,and the optimization measures for the operation mode of the system are discussed for the problems found.In order to study the operating characteristics of the air source heat pump hot water unit the subject was tested under different operating modes in summer,transitional season and winter.In the summer cooling and hot water mode,the heat absorption of the hot water in the water tank is provided by the recovered unit’s condensing waste heat.It is completely free of charge.There are two types of end units:the unit is provided when the fan coil is cooled.The average EER is as high as 5.4,and the average EER of the unit is 5.8 when the floor is radiant.In both end forms,it takes about 30 minutes for the unit to heat 200L of water from 30℃ to 50℃.When the unit is only used for the domestic hot water mode during the transitional season,the unit heating efficiency is greatly affected by the outdoor temperature.In the transitional season,it takes about 45 minutes for the unit to heat 200L of water from 15℃ to50℃,and the average EER of the unit is 3.35.In winter,the unit has two modes of operation:one is a separate heating mode,in which the unit heats the same volume of water from 10℃ to 50℃ for about 1.3 h,and the EER average is 2.72;the other is At the same time of hot water production mode,the average EER of the unit with heating and hot water mode at the end of the wind disk is 2.34,and the average EER of the floor radiant end heating and domestic hot water mode unit is 3.39,and the heating time is 1.5h.The experiment proves that the multi-function air source heat pump hot water unit can run stably under different working conditions and modes.The energy efficiency of the unit operation is relatively high and the energy saving effect is remarkable.In addition,this topic uses the software MATLAB to write a mathematical simulation program of the multi-function air source heat pump hot water unit,and carry out simulation and calculation.The simulation results show that the annual energy efficiency ratio of the multi-function air source heat pump hot water unit is 3.85.By optimizing the air source heat pump system,the heat recovery of the summer unit can not only produce free hot water but also water cooling and condensation.The unit hot water tank combined with the small temperature difference floor radiant heating,greatly improved the unit operating efficiency.After economic analysis of the simulation results of the unit,the results show that the annual operating cost of the domestic hot water produced by the unit is 17%of that of ordinary electric heating water heaters,36%of gas water heaters,and has considerable market prospects. |
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