|Budget Amount *help
¥2,200,000 (Direct Cost : ¥2,200,000)
Fiscal Year 1996 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1995 : ¥1,700,000 (Direct Cost : ¥1,700,000)
In this investigation, the Marangoni effect in two-component heat pipes under a ground condition were discussed. A rectangular heat pipe which was mode of glass and contained an ethanol solution as the working fluid was used for experiments. The behavior of the working fluid in the heat pipe under operation was observed by schlieren system. As the results, it was found out that the condensing pattern of the working liquid differed with the ethanol concentration, namely, dropwise for 5 mol%, dropwise or stripewise for 20 mol%, stripewise for 50 mol% and filmwise condensation for 85 mol% in ethanol concentration. Although ethanol was soluble in water, dropwise condensation was observed for dilute ethanol mixture, and the condensed drops were traveling from cooling to heating part with the velocity of about 2 mm/s for the results of 5 mol% ethanol solution. These are thought to be the cause of the Marangoni effect by concentration difference. These results show the potential of two-component heat pipes utilizing the Marangoni effects, which are available without wicks, even in a microgravity environment.