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本文针对铜珠堆积表面,研究高碳醇水溶液浓度w、铜珠直径φ和铜珠层数N对气泡行为和沸腾传热曲线的影响.结果表明,对于水,达到一定铜珠层数后气泡生长通道基本被阻隔;对于溶液,存在气泡井喷现象.对于水,N=1时存在临界直径可极大强化传热;N=4～7时沸腾曲线整体趋势一致且比N=1时明显偏左.对于溶液,N=2时沸腾曲线偏左于水且随w增加而总体偏左;N=3时,若孔隙率渐变大,沸腾曲线偏右于水,但差异较小.随热流密度增加,溶液甚至出现传热恶化现象.“,”The effects of mass fraction (w),and diameter (φ) and layer number (N) of copper beads on pool boiling heat transfer characteristics of high-carbon-number alcohol solutions over packed-copper-bead surface were studied.It shows that the bubble growth for water can be hindered when the layer numbers of copper beads reach a certain value,while for the solutions there exists the bubble blowout phenomenon.For water,there exists a critical diameter at which the boiling heat transfer can be optimally enhanced when N=1;and the boiling curves are basically the same but obviously left-shifted when N=4～7.For the solutions,the boiling curves shift left as compared to water when N=2,and the left-shift intensifies as w increases;while,with gradient porosity,the boiling curves shift right as compared to water when N=3,although the deviations are small.The boiling heat transfer of the solutions can be even deteriorates with increasing heat flux.