Bubble nucleation in microchannels: statistical mechanics approach

Microscale boiling displays quite some unusual characteristics, like the occurrence of the so-called “fictitious boiling”. This paper modeled the bubble embryos occurring during microchannel boiling using a statistical mechanics approach. The bubble nucleation temperature of working liquid heated in a microchannel was theoretically derived. Experimental efforts were conducted to measure the nucleation temperatures for four working fluids (water, methanol, ethanol and carbon tetrachloride) boiled on a platinum wire confined in capillary tubes. Both theoretical and experimental findings demonstrated that the bubble nucleation temperature markedly increased as the size of microchannel went down. Regression analysis of experimental results estimated the process parameters in the theoretical prediction.