The Property Research Of The Coiled Tube Heat Exchanger

With the rapid development of economy,China's demand for energy has increased dramatically.How to make use of energy scientifically and attain the goal of energy conservation has become the focus and competition of every nation.While in the areas of industrial engineering,most of the energy conversion and transmission has to be implemented through the heat exchanger,so the study of high efficiency and energy saving heat exchangers is increasingly important.Due to its characteristics of compact structure,high efficiency,high pressure resistance and multiple flows of heat transfer,the coiled tube heat exchanger is widely used in petrochemical,air separation,nuclear power,chemical industry and other fields.However,due to its complicated structure and the special manufacture method,domestic and foreign research is not thorough enough,therefore the heat transfer and flow characteristics of the coiled tube heat exchanger and the influence of various factors on heat transfer is unclear.So in order to designed the satisfactory high efficient coiled tube heat exchanger,and clear its heat transfer mechanism,it is necessary to do comprehensive studies on the flow and heat transfer characteristics of the coiled tube heat exchanger.Based on this idea,this paper will proceed with two aspects which are experimental research and numerical simulation.The research content is as follows:1.Use multi-functional test-bed to combine designing specific experimental steps and experimental data processing method with experiment device principle,in order to lay the theoretical foundation for follow-up studies.2.Control the heat exchangers' heat transfer area as 1 m2 and do research on heat transfer and flow resistance performance of the coiled tube heat exchanger with plain tube and screwed tube respectively,then compare the performance with the traditional shell and tube heat exchanger by changing the tube side and shell side flow rate,heat side and cold side fluid inlet temperature and the "cold and hot fluid in the heat exchanger process.And do research on the pressure drop of three kinds of heat exchangers in the same case of tube and shell side's flow rate.3.Make use of Solidworks software to build the coiled tube heat exchanger's model at the same size,and import the model to the Floefd software for simulating the temperature,pressure,and flow field.4.Rebuild the model through the changes of geometrical parameter such as layer spacing,tube spacing,and the length-diameter ratio of the heat exchanger,in order to observe the influence of the changes of geometric parameters on heat exchange's performance and the pressure drop,and to analyze the main factors of influencing the coiled tube heat exchanger's fluid flow heat exchange performance.