抄録
This paper concerns the condensation of carbon dioxide and its heat transfer on a vertical surface in the subcritical region. In this region, physical properties show a marked temperature and pressure dependence. In particular, as the pressure increases and approaches the critical pressure, the difference in density between liquid and vapor, and surface tension approach zero. Therefore the condensates flow and heat transfer may differ from those for lower pressure. In this study, the heat transfer was obtained and the state of the condensate flow was observed in detail. As a result, the condensate flow is classified into five regimes : the smooth laminar flow, wavy flow, wavy flow with sharp crest, wavy flow with scattered droplets and wavy flow with scattered mist. Experimental heat transfer is compared with the Nusselt theory. The influence of the pressure and condensate flow on heat transfer are also discussed.
