研究期間：10207~10212;Owing to the High Global Warming Potential Value, the conventional HCFC and HFC refrigerants will be phased out in the near future. The recent developed low GWP HFO refrigerant should be the most important refrigerant to be used in the next generation air condition systems. This project provides a systematical study on the heat transfer and flow characteristic of refrigerant HFO-1234yf. It includes the experimental measurement of the single-phase liquid, convective boiling and condensation heat transfer performance of refrigerant HFO-1234yf inside tubes as well as pool boiling on plain and enhanced surfaces. The condenser and evaporator heat exchanger design programs will be developed based on the heat transfer performance tested in this project. The type and specification of compressor and expension devices will slao be selected and adjusted. The overall results will end up to a computer program for HFO refrigerant air condition system design. It can be applied for HFO air condition system design by the related domestic manufacturers. This study is expected to be the leading research all over the world in the field of HFO refrigerant.