流路内高温域噴霧流による冷却技術に関する研究 -冷却特性の実験的算定および解析結果との比較- Two-phase Mist Flow Cooling in the Tube with High Wall Temperature -Experrimental Estimation of the Cooling Characteristics Compared with the Analytical Results-
In order to apply the two-phase mist flow for the purpose of uniform and mild cooling of the high temperature walls in such advanced power systems as high temperature fuel cells, turbines and large Diesel engine with ceramic material, the cooling characteristic of the mist flow, especially the apparent large heat capacity of the coolant, is investigated experimentally in the high temperature tube and compared with the analytical results. An empirical correlation for the ratio of heat removal by impinging liquid droplet on the heating wall surface to the total heat flux was obtained from the experimental data. It is found that the ratio is mainly determind by gas Reynolds number, gas quality that means mass fraction of gas phase and the surface temperature. In the high wall-temperature range, a newly defined coefficient of the gas temperature increase was obtained experimentally and compared with the analytical results which was described in the former paper. The coefficient is found to decrease with the increase of liquid mass fraction and not to depend on the gas velocity. The tendency coincides qualitatively with that of the analytical results. The cooling characteristic of the high temperature mist flow was clarified from these considerations.
日本舶用機関学会誌 31(4), 233-238, 1996-04-01
The Japan Institute of Marine Engineering