Counter-Current liquid and gas flow in finned compact heat exchangers with offset strip fins
Résumé
Although flow boiling in small channels was intensively investigated, the influence of binary mixture composition on flow boiling in microscale has not been widely studied so far. The aim of this study is to investigate heat transfer to binary mixtures in finned compact evaporators. Three coupled physical phenomena are examined: thermodynamic (mixture vaporization), hydrodynamic (two-phase upward flow) and interphase mass and heat transfer. An experimental rig is being designed to study the upward vaporization of binary mixtures. The fluids tested are either HFC (mixture of R-134a and R-245fa) or hydrocarbons. The test section is an electrically-heated passage with serrated fins which allows flow regimes visualization. In this paper, a review about flow boiling of mixtures will be presented as well as the description of the experimental apparatus and the goals behind this study.