Optimization Design Of Evaporative Condenser And Performance Study Of Heat Pump Unit

With the continuous development of society,energy and environmental issues have become increasingly prominent.In the field of air conditioning,refrigeration and heating,reducing equipment energy consumption and improving operational performance are of great significance for reducing energy consumption.Evaporative condensers are widely used in various fields of refrigeration due to their excellent performance and good performance in energy saving and water saving.Air source heat pumps are widely used in recent years because of their use of air energy and their high energy efficiency ratio,especially in the field of clean heating.In the process of using the evaporative condenser,because the technology is not very mature,there are still many problems,which cause a lot of troubles for its use.If they can be optimized to improve the technical level,to improve the performance and applicability,match the source heat pump,consisting of evaporative cooling air source heat pump,with the unit for efficient use of energy,there is great practical and economic value.In this paper,the existing problems of evaporative condensers are analyzed from the theoretical level.Starting from the structural design,an optimization solution is proposed,and an evaporative condenser with a V-type pre-cooling heat transfer structure is designed.Due to the design of the V-type pre-cooled heat exchanger coil,its performance has been greatly improved.Great changes have been made in energy saving,water saving,scaling delay,cooling water flow,etc.,and it has also improved its application range.It can be used for dry operation in air heating conditions in winter,for air-cooled evaporators.Provide a sufficient heat source for the heating system.And it is matched with the air source heat pump to design the integrated machine.Perform an experimental test of the running performance of the prototype.After experimental tests,under the heating condition,the working performance is stable.When the ambient temperature is-16 °C,the COP can reach 2.73;Under refrigeration conditions,when the ambient temperature is 40 °C,the refrigeration COP can reach 4.08.Under the hot and humid environment,the system can run stably and the refrigeration performance is good.The optimized design of the evaporative cold condenser is more suitable for the air source heat pump than the general air source heat pump unit to obtain the cold heat source.The working range is wider and the working performance is more stable in the extreme weather.The experimental performance of the evaporative cooling air source heat pump cooling performance was also tested.It is found that changes in the evaporator inlet water temperature t,compressor frequency f,air dry bulb temperature t ",wind speed v,water spray speed v",etc.have a great influence on its performance.The experimental results show that the increase of evaporator inlet water temperature,wind speed and water spray speed can increase the cooling capacity Q and COP,and the increase of air dry bulb temperature and compressor frequency will reduce COP.When the wind speed increased from 2m/s to 4m/s,the COP increased by 15.5%,and the water spray speed increased from 0.03 kg·m-1·s-1 to 0.05 kg·m-1·s-1,the COP increased.7.4%,the heat transfer coefficient K increases from 232w/m2·k to 398w/m2·k.