Effect Of The Passage Area Ratio Of Wick On An Ultra-Thin Vapour Chamber With A Spiral Woven Mesh Wick

The effect of passage area ratio of wick on the heat transfer performance of the ultra-thin (0.4 mm-thick) vapour chamber (UTVC) which fabricated by brazing bonding was experimentally investigated, the spiral woven mesh (SWM) was utilized as the wick structure and support for the steam chamber of UTVC. The passage area ratio of wick of UTVC was adjusted by changing the number of SWMs. The capillary limits of UTVCs with different passage area ratio of wick were analyzed theoretically. The effect of SWM number and test direction on the thermal performance of UTVCs was experimentally investigated. The results indicated that the maximum heat transport capacity of UTVC increased and then decreased with increasing SWM number. An appropriate SWM number was beneficial to enhance the UTVC's thermal performance by increasing the vapour-liquid circulation efficiency during heat transfer. The maximum heat transfer capacity of UTVC with 3 SWMs under gravity test direction was 6 W, which was 2 times, 1.4 times, and 1.3 times that of UTVC with SWM number of 1, 2, 4, respectively. The maximum heat transfer capacity of UTVCs changed by less than 10% under different test directions. The optimum passage area ratio of wick of the experimental UTVC was 62.5%.