| In an era of massive global energy consumption,in order to achieve the goal of stabilizing the global temperature rise at 1.5℃,China should increase the investment and utilization of renewable non-fossil energy and reduce the consumption of fossil energy development.Solar energy and air energy are high quality energy that can be used in large quantities,and the application technology is gradually becoming mature.The combination of solar energy and air source heat pump heating system can effectively solve the problem of heating resource consumption,which accounts for up to 65%of building energy consumption.The two kinds of environmental protection energy complement each other to achieve the purpose of energy saving and emission reduction.In this paper,starting from the analysis of the performance of the solar-air source heat pump heating system,an experimental platform of the solar-air source heat pump heating system was built in Tianjin to explore the parameter changes of the system when the electric heating wire and the air source heat pump heated water to different temperatures.Further analysis of the air source heat pump system under different initial pressure and throttle valve opening conditions,find out the best operating state parameters of the air source heat pump system;Then the simulation software was used to expand the monthly change rules of power consumption and heat production at different water supply temperatures.The experiment explores the water temperature and daily useful heat gain of the heat storage tank under different weather conditions when only solar collector was used for heating in summer.Based on the simulation platform,the daily useful heat gain and collector efficiency of water tanks with different volumes during the operation of the whole year were explored.The influence of the height of the spiral pipe in the water tank on the solar energy-air source heat pump heating system was analyzed,and the influence of the two kinds of water tanks on the power consumption of the heating system,the heat production and the COP of the system are explored by using the simulation platform.In three coastal cities of Tianjin,Shanghai and Shenzhen,the monthly power consumption of the heating system,the heating quantity,the COP of the system and the COP of the heat pump unit are simulated when the plate collector and vacuum tube collector are used in series and parallel connection with the air source heat pump heating system in Tianjin,Shanghai and Shenzhen.Within the research scope of this paper,the main conclusions were as follows:(1)The experiment explored the power consumption of heating 0.1m~3 and 0.2m~3water by electric heating wire and heat pump at different set temperatures.Heating 0.1m~3of water to 80℃by electric heating wire consumed 7.64k Wh,which was 16.26 times that of heat pump heating.When the electric heating wire heatd 0.2m~3 water to 80℃,the power consumption was 16.07k Wh,which was 10.11 times of the power consumption of heat pump heating.Heat pump heating method had higher advantages in energy saving than electric heating wire heating method when the setting temperature was higher.(2)The initial pressure and the size of the throttle valve opening have an impact on the heat production and power consumption of the air source heat pump system,and the initial pressure had a greater impact on both.Under the same throttle valve opening,the COP of the unit was the minimum when the initial pressure was 4.5MPa,and the maximum when the initial pressure was 6MPa.The simulation calculation of air source heat pump showd that the COP increased first and then decreased with the increase of the set temperature,and the higher the ambient temperature,the higher the COP.When the effluent temperature was set at 55℃,COP coluld reach the maximum in each month.When the temperature was set at 65℃,the COP of each month was the minimum.The changes of the maximum and minimum COP in different months were 30.67%in January,27.15%in April,24.73%in July and 26.48%in October.Within the scope of this research,it was found that the best operation mode of the air source heat pump system was the initial pressure of 6MPa and the throttle valve was fully open.The COP of the heat pump system was the highest when the temperature was set at 55℃and it was run in July.(3)The experimental investigation on the solar collector showd that the temperature in the water tank increases gradually with the extension of time.The temperature in the water tank reached the highest at about 16:30 in the afternoon when the amount of solar radiation was strong,and the temperature in different environmental conditions was above 55℃.The simulation results for the solar collector showd that the maximum Q_Uvalue decreased by 0.37%and the maximum P value decreases by 6.62%with the increased of the tank volume in April.It could be seen that solar collectors in Tianjin could provide hot water with higher temperature,especially in summer,so they should be utilized and promoted.(4)The experimental research resulted of the solar-air source heat pump system showd that:under the same working condition,the COP of the heat pump system of the1.5m spiral pipe heat exchange tank was calculated as 18.71%higher than that of the0.75m spiral pipe heat exchange tank system.The simulation results showd that the COP of 1.5m spiral water tank system was 4.35%higher than that of 0.75m spiral water tank system(the highest)in July.In February,COP of 1.5m spiral pipe water tank system was2.87%higher than that of 0.75m spiral pipe water tank system(the lowest).In the solar energy-air source heat pump heating system,the use of 1.5m spiral pipe heating tank had more obvious advantages of energy saving.(5)The solar energy-air source heat pump heating system,which adopted the vacuum tube collector,flat plate collector and the series and parallel connection of the heat pump system,was applied to residential buildings in specific geographical locations.The results showd that:Taking the combined operation of vacuum tube collector and air source heat pump as an example,the COP of unit and system increased by 15.81%and11.03%with the decreased of regional latitude.Taking Tianjin as an example,the COP of the unit with vacuum tube collector and air source heat pump in parallel increased by7.98%and 6.91%compared with that with vacuum tube collector and air source heat pump in series.The COP of the unit with vacuum tube collector was increased by 0.21%and the COP of the system was increased by 25.54%compared with that of the unit with plate collector.Therefore,if the heating system chooses vacuum tube collector and air source heat pump to run in parallel,the energy saving was better.When the solar-heat pump system runs in Shenzhen,the performance parameters of the heating system are better than those in Shanghai and Tianjin. |
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