关键词: 并联式脉动热管, 倾角, 充液率, 传热性能

Abstract: With ultrapure water as working medium, the heat transfer characteristics of parallel type pulsating heat pipe with three different liquid filling ratios (35%, 50% and 70%) and two different inclination angles (60°and 90°) were investigated experimentally and analytically. On the basis, the effect of liquid filling ratio and inclination angle with different heating powers on the properties of parallel type pulsating heat pipe, namely wall temperature,temperature difference of heating section and condensing section, heat transfer quantity and thermal resistance were studied. Meanwhile, the uncertainty of thermal resistance was also calculated. The experimental results show that liquid filling ratio and inclination angle can effectively influence heat transfer characteristics of pulsating heat pipe. When the inclination angle was 90°, on the condition of different liquid filling ratios, pulsation stability of wall temperature with liquid filling ratios of 35% and 50% were superior to that of 70%. When the liquid filling ratio was 50%, the thermal resistance and temperature difference of heating section and condensing section were the smallest. On the contrary, when the liquid filling ratio was 70%, the corresponding thermal resistance and temperature difference were the largest. In addition, with liquid filling ratio of 50% and inclination angle of 60° and 90°, pulsation range of wall temperature and thermal resistance with 60° were large, and the corresponding heat transfer limitation became narrow with the same heating power comparedwith inclination angle of 90°. Therefore, heat transfer effect with liquid filling ratio of 60° was obviously worse than that with liquid filling ratio of 90°.

Key words: parallel type pulsating heat pipe, inclination angle, liquid filling ratio, heat transfer characteristic