Experimental investigation on the heat transfer performance and evaporation temperature fluctuation of a new-type metal foam multichannel heat pipe

摘要

Recent electronic industry developments require a variety of compact and high-performance heat sinks for the heat dissipation of electronic devices. In this paper, on the basis of a new type of heat pipe called the metal foam multichannel heat pipe (metal foam MCHP) proposed by our team, an experimental apparatus on its heat transfer characteristics was built. The heat transfer characteristics of the metal foam MCHP with the distilled water as the working fluid were experimentally investigated in a heat flux range of (18750-112500) W/m~2, a filling ratio range of 0.1-0.6 and single-sided/double-sided heating modes. The experimental results showed that the working fluid could flow up and down in the metal foam MCHP, and thus the heat was transferred from the evaporation section to the condensation section during the operation. The thermal resistance of the metal foam MCHP decreased with the increase of the heat flux. When the heat flux was up to 112500 W/m~2, the thermal resistance decreased to 0.142 °C/W. The optimal filling ratio of the metal foam MCHP charging with the distilled water was 0.2. During the experiment, the temperature fluctuations of each measuring point in the evaporation section were almost within 2 °C and the temperature differences of different measuring points in the evaporation section were within 8 °C. The thermal resistances of the metal foam MCHP under the single-side heating mode and the double-sided heating mode were compared, and the thermal resistance of the metal foam MCHP was found to be higher under the single-sided heating mode. In addition, compared with the traditional PHPs, the metal foam MCHP showed better heat transfer performance and better stability and uniformity of the evaporation temperature.