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ISSN Online: 2377-424X

ISBN Print: 978-1-56700-421-2

International Heat Transfer Conference 15
August, 10-15, 2014, Kyoto, Japan

Study of Heat Pipe Effectiveness Filled with Different Refrigerants

Get access (open in a dialog) DOI: 10.1615/IHTC15.hex.009194
pages 3651-3662

Resumo

Nowadays, heat pipes are gaining more and more attention in the construction of heat exchangers used in various devices for heat recovery in ventilation systems, heating, air conditioning, refrigeration, etc.). Carried out studies will be utilized in construction of high-performance heat exchangers. Heat exchange processes are taking place in the heat pipe both in the place of heat addition side (evaporator) and the heat receiving side which is the condenser section. Aim of scientific research is to understand the results of phase transitions taking place in the heat pipe and to determine its effectiveness for different working conditions. Tests were carried out for different refrigerants, such as R134a, R404a, R407c, with different filling volumes of tested heat pipe with working fluid. Evaporator part of the heat pipe is heated with water at different temperatures, and the condenser part is cooled with liquid at a constant temperature. On the basis of research results, ranges in which the heat pipes work with the greatest efficiency, have been identified. Heat pipe worked most efficiently filled with 404a refrigerant with highest efficiency (75 ÷ 83%) and high heat throughputs for all considered filling ratios. The heat pipe operates properly in the range of temperatures: 293 to 323K, with this working fluid. Good heat transport properties of the heat pipe is also achieved with the use of refrigerant R134a The advantage of working with R134a is lower operating pressures than R404A for about 300000 ÷ 600000 Pa. The highest heat fluxes were obtained for R134a at filling ratio: 10%, lowest for 40%. Heat pipe filled with refrigerant R407c is least efficient.