Freezing And Melting Process Research Of Ice Thermal Storage Air-conditioning System

Ice thermal storage air-conditioning is an important measure of transforming a part of peak loads of the day to valley loads of the night. It is also an interesting development direction of modern air-conditioning. It can improve the energy sources utilization efficiency and optimize resource configuration through producing at the night and consuming in the day. It contributes much to economic construction and levels the electric power loads.The study situation of ice thermal storage air-conditioning system was reviewed, on the basis of summarization of coldness storing technology, the following work was done:1. Starting with basis phase change theory, the basis principle and process were stated, and theoretical analysis was done, basing on the simplified mathematical mode, energy balance was analyzed, approximate analysis method was taken to get the result and working curve of coldness storing and releasing working condition were got.2. By measuring the parameters of temperature, flow rate, compressor electric current, and voltage and so on, study on the ice-freezing, ice-melting and conventional of air-conditioning was carried out. By experiment data treating, the rule by which the ice thermal storage system parameters vary according to time was obtained, and the system characteristics of ice-freezing and ice-melting and the influencing factors and trend were analyzed deeply. The results of theoretical calculation and experiment were compared and analyzed.3. Engineering was used as an example to compare and discuss different operation modes and control strategies. Performances of various ice freezing modes of ice thermal storage air-conditioning system were analyzed, compared and evaluated. According to ice thermal storage air-conditioning system characteristics, economic analysis and comparison were made between conventional air-conditioning and ice thermal storage air-conditioning. Various technological and economic indexes of icethermal storage air-conditioning system were calculated. Based on the electricity charge contraction in Jiangsu, current electric price structure's influence on running fee was calculated. These analyses have great reference value for ice thermal storage system research, design and diagnose of running thermal storage system.While stating the system properties, specific and accurate data was quoted to assure the owner and power department that the ice thermal storage technology is feasible and effective. We hope that this paper can do something to help the development and popularization of the thermal storage air-conditioning, and can help the design and operating of ice thermal storage system.