Study On The Performance Of Supercooling Water Source Heat Pump Heating System

With the implementation of the"Coal power conversion"policy,heat pump as an efficient andenergy-saving heating method,has been used by more and more countries and people.However,there are some problems in the application of heat pump,for example,the problem of low efficiency when the air source heat pump is used in the cold winter area,the water source heat pump is limited by the winter water temperature of shallow groundwater,it is difficult to exert the advantage of high efficiency heating,and the water consumption is very large,which is difficult to be used Aiming at the above problems,based on the research of heat pump system and supercooled water dynamic ice making system,a supercooled water source heat pump heating system using water phase transformation energy is proposed,and its performance is tested.The main contents are as follows:Firstly,the heating system of a rural residence in Tie Ling,Liaoning Province is used as the prototype,and the simulation model of heating system is built based on TRNSYS software,and the indoor and outdoor temperature changes of residential buildings in heating season are simulated and analyzed,as well as the energy consumption of system heating.Secondly,the experimental platform of the supercooled water source heat pump heating system is built,the system selects the Grain Wheel scroll compressor,the input power is 4.78 kW,the capacity is 11.1 kW,all the parts of the system are matched by the heat production of 5compressors,the performance of the heat pump system is analyzed,and the heating is measured,the results are as follows:(1)By comparing the changes of heat production under variable flow,it is found that the rate of change of heat production decreases gradually with the increase of traffic flow.The rate of heat production increased from 4 m~3/h to 4.2 m~3/h was 8%lower than that of 3.6 m~3/h when it increased to 3.8 m~3/h.It shows that the influence of heating flow on heat production is less and less.(2)With the increase of heating temperature,the heat production of the system decreases and the input power of the compressor increases.When the heating temperature is 40~45℃,the COP is relatively stable,but more than 45℃,the thermal performance coefficient decreases significantly,and when the heating temperature rises to 55℃,the COP is reduced by 24%.(3)With the decrease of water source temperature,the evaporation pressure of the systemdecreases,the condensation pressure increases,and the water source temperature reaches the supercooled state,the evaporation pressure will remain at 3.5 bar.At this time only the heating temperature has an effect on the condensation pressure,which has little effect on the evaporation pressure.Compared with the air source heat pump,this system has the advantage of high energy efficiency of the system when it is used in winter.(4)A heat recovery device is designed,and the heat capacity increases the 14.8%,COP by10.7%compared with the no-return fuser system.The effect of using low preheating temperature to achieve high heat capacity and energy efficiency ratio is realized.(5)In the coldest weather,when the temperature-17~-10℃,the selection of three average heating temperature for performance analysis,with the increase in heating temperature,the system power consumption increased,but the water consumption decreased,from 43.5℃to53.7℃,daily power consumption increased by kWh,and the amount of ice production from the kg/h to the kg/h,The minimum indoor temperature was increased from 16.7℃to 18.5℃.Finally,from the aspects of economy and energy saving,the feasibility of application of supercooled water source heat pump heating system is verified,and the results show that the annual cost of cold water source heat pump heating system is 56.2%and 12.6%lower than that of electric boiler and air source heat pump respectively,and the payback period of investment is shorter than that of electric boiler heating.From the energy-saving point of view,compared with the heating of coal-fired boilers,the heating season saves coal 593.3 kg.Compared with the water source heat pump heating system,the water consumption is reduced by 91%,which greatly reduces the pollution and consumption of aquatic resources.In this paper,the operating characteristics of the supercooled water source heat pump heating system are analyzed by means of simulation and experiment,and the heating measurement is carried out to verify the accuracy of the simulation.It provides a certain basis for the design and optimization of this kind of product,and has certain reference value for popularizing the heating method.