Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
648401 | Applied Thermal Engineering | 2009 | 13 Pages |
Abstract
Two-phase frictional pressure drop characteristics of R410A/oil mixture flow boiling in horizontal small smooth tubes with outside diameters of 5.0 mm and 3.0 mm were investigated experimentally. Experimental conditions cover nominal oil concentrations from 0% to 5%. The test results show that the frictional pressure drop of R410A initially increases with the increase of vapor quality and then decreases, presenting a local maximum in the vapor quality range between 0.6 and 0.8; the presence of oil increases two-phase frictional pressure drop about 0-120% and 0-90% in present test conditions for 5.0 mm O.D. smooth tube and 3.0 mm O.D. smooth tube, respectively, and the increase is evident at high vapor qualities. The vapor-phase multiplier of R410A/oil mixture based on the mixture properties decreases with the decrease of tube diameter. A new vapor-phase multiplier correlation to predict the local frictional pressure drop of R410A/oil mixture flow boiling inside smooth tubes is developed based on local properties of refrigerant-oil mixture, and the deviations of the new correlation are within ±25% from the experimental data.
Keywords
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Fluid Flow and Transfer Processes
Authors
Hai-tao Hu, Guo-liang Ding, Xiang-chao Huang, Bin Deng, Yi-feng Gao,