Simulating a porous surface that is partially saturated with a liquid, a two-dimensional meniscus attaching two adjacent cylinders with the same diameter is studied under heating and convective conditions. It has been recognized that in a region that connects the meniscus to the heated surface, there exists a thin film region that is responsible for high heat transfer rate. The quantitative information on thin film characteristics such as thin film length (Tao et al. 1998) and heat transfer rate will help understand the control mechanism of thin film and better design of heat transfer devices. In this study, the conduction in cylinder and convective heat transfer in the fluid are analyzed using a commercial CFD finite element code, COSMOS/M with the FLOWPLUS option. Ethanol is chosen as calculating liquid. As a boundary condition, the surface temperature model of the liquid meniscus and exposed cylinder is established. The effects of Bond number, spacing between cylinders and heating power on thin film geometry and transition region are discussed. Correlations to predict the evaporative heat transfer coefficient and the ratio of evaporative heat transfer rate to the total heat rate are presented.
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