Analysis And Optimization Of Evaporative Air Cooled Chiller

Building energy consumption occupies an important proportion in the country’s total energy consumption. Reduce building energy consumption is an inevitable requirement for the energy and environment sustainable development of our country. Air conditioning energy consumption is the main body of the building energy consumption, so reduce air conditioning energy consumption has great significance to the promotion of building energy conservation and emission reduction. Air-cooled chiller has the advantages of compact structure, simple system, convenient installation and low investment cost; therefore it has been more widely used in the small and medium-sized construction. But compared with water-cooled water chiller, air-cooled water chiller is not conducive to building energy efficiency due to its low efficiency. So this paper tries to improve the energy efficiency of air-cooled water chiller to make it more efficienct by adopting a simple, reliable and effective method.Evaporative air-cooled water chiller is the combination of direct evaporative cooler with air-cooled water chiller. The direct evaporative cooler condenser can reduce inlet air temperature and then reduce the condensing temperature, thus enhancing the energy efficiency. Based on the mathematical model of direct evaporative cooler and air-cooled water chiller, this paper use MATLAB to write program and analyzes influence factors of the performance of the evaporative air-cooled water chiller. These factors include climatic conditions, face velocity, and the thickness of the filler. In order to evaluate the energy saving potential of evaporative air-cooled water chiller in china more accurate and reasonable, this paper take ISEER as evaluation index, which is the optimization goal. This paper optimizes the filler thickness, and gives the best filler thickness of the evaporative air-cooled water chiller in our major cities.For further consideration of the chiller load changes along with the building load and the energy-saving potential of the chiller under different control strategy, this paper also establishes the detailed analysis model of the evaporative air-cooled water chiller, analyzes the energy saving potential of chiller under different load rates through that model. For further help engineers to analyze and design evaporative air-cooled water chiller, this paper develops calculation software package for chiller based on theoretical analysis. Through the research of this article, and draw the following conclusions:(1) There is an optimal filler thickness which can make the chiller achieve the best performance when climate and face velocity are under certain condition. In allusion to climate conditions in China, best packing thickness is between80～140mm.(2) The performance of evaporative air-cooled water chiller is strongly influenced by load rate and the cooling control strategy. Comparative analysis showed that the energy-saving potential under variable condensation temperature control is higher than constant condensation temperature control.(3) Optimization of the evaporative air-cooled water chiller has a high energy saving potential than traditional air-cooled water chiller, it has great application prospects, and has great energy saving potential especially in the northern and western areas in China.