Condensation and evaporation heat transfer of R410A inside internally grooved horizontal tubes |
| |
Authors: | M Goto N Inoue N Ishiwatari |
| |
Affiliation: | Tokyo University of Mercantile Marine, 2-1-6, Etchujima, Koto-ku, 135-8533, Tokyo, Japan |
| |
Abstract: | Heat transfer coefficient and pressure drop were measured for condensation and evaporation of R410A and HCFC22 inside internally grooved tubes. The experiments were performed for a conventional spiral groove tube of 8.01 mm o.d. and 7.30 mm mean i.d., and a herring-born groove tube of 8.00 mm o.d. and 7.24 mm mean i.d. To measure the local heat transfer coefficients and pressure drop, the test section was subdivided into four small sections having 2 m working length. The ranges of refrigerant mass flow density was from 200 to 340 kg/(m2 s) for both condensation and evaporation of R410A and HCFC22, and the vapour pressure was 2.41 MPa for condensation and 1.09 MPa for the evaporation of R410A. The obtained heat transfer data for R410A and HCFC22 indicate that the values of the local heat transfer coefficients of the herring-bone grooved tube are about twice as large as those of spiral one for condensation and are slightly larger than those of spiral one for the evaporation. The measured local pressure drop in both condensation and evaporation is well correlated with the empirical equation proposed by the authors. |
| |
Keywords: | Heat transfer Mass transfer Condensation Refrigerant R410A horizontal tube Inside Enhances Heat transfer coefficient MeasurementTransfert de chaleur Transfert de masse Condensation Frigorigè ne R410A Tube horizontal Inté rieur Surface augmenté e Coefficient de transfert de chaleur Mesure |
本文献已被 ScienceDirect 等数据库收录! |