In order to investigate the evaporation heat transfer characteristics in heat transfer tubes,the experimental study on heat transfer characteristics of R410 A in copper and stain-less steel smooth tubes and corrugated tubes was carried out in this paper.The heat transfer mechanism of partial flow pattern to evaporation in tube is analyzed.The experimental con-ditions are:the saturation temperature is 6℃,the mass flow rate of refrigerant is 100-200 kg·(m2·s)-1,and the vapor quality range is 0.1-0.9.The flow patterns in smooth tubes are verified,and the results are in good agreement with the predictions of Wojtan flow pat-terns map.The experimental results show that the evaporation heat transfer coefficient in-creases with the increase of mass flow rate.Heat transfer coefficient is related to flow pat-tern.Pressure drop mainly depends on mass flow rate and vapor quality.Compared with the smooth tube,the heat transfer enhancement rate is 1.27-1.96,and the boiling pressure drop increases by 11%—36%.
关键词
蒸发换热/三维强化管/换热系数/压降
Key words
evaporation heat transfer/three-dimensional enhanced tube/heat transfer coeffi-cient/pressure drop
维普
万方数据