III. ULUSLARARASI MESLEKİ VE TEKNİK BİLİMLER KONGRESİ, Gaziantep, Turkey, 21 - 22 June 2018, pp.284-291
In the present study, the effects of filling ratio and inclination angle on the thermal
performance of a circular wicked heat pipe are investigated experimentally. The length of the heat pipe is 172 mm; while the lengths of the evaporator, adiabatic and condenser sections are 42 mm, 46 mm and 84 mm, respectively. Container is made of copper, while the wick is made of stainless steel. Ethanol is used as the working fluid. Experiments have been conducted for different filling ratios (40%, 60% and 80%) and inclination angles (0° ve 90°) under different thermal powers (2.5 W – 18.5 W). It is concluded that thermal resistance decreases with increasing thermal power for all the conditions in the experimental range. The lowest thermal resistance is obtained for the filling ratio of 60% for both of the horizontal (0°) and vertical (90°) orientations. The values of the thermal resistance for the filling ratio of 40% are quite higher than the ones of the other filling ratios. The thermal resistances in the vertical orientation are significantly lower than the ones in the horizontal orientation. However, the
heat pipe can work even only with the effect of capillary force (without the gravity assistance, in horizontal orientation, 0°). Also, the temperatures of the evaporator and condenser sections in vertical orientation are lower and higher than the ones in the horizontal orientation, respectively.