Speaker
Description
Liquid-vapor multiphase flow and its phase change in porous media are widely applied in engineering fields, such as transpiration cooling of high-speed aircraft, heat removal of chip stacks, proton exchange membrane fuel cells, etc. In this presentation, by utilizing the hybrid lattice Boltzmann method, the mechanisms of coupled liquid-vapor two-phase flows, phase change and heat/mass transfer in porous media are studied at pore-scale. First, the numerical modeling framework is introduced. Afterwards, three types of phase change processes, i.e., evaporation, boiling and condensation in porous media are introduced in sequence. For evaporation, the various evaporation patterns are studied, governed by the competing mechanisms between capillary flow and local evaporation strength. Evaporation-induced particle deposition and its effect on cooling of 3D chip stacks is also studied. For boiling, three different boiling regimes and corresponding heat transfer in simple porous media are investigated. Compared with pool boiling, the nucleation temperature, critical heat flux and effective boiling temperature range are analyzed. For condensation, the competing mechanism between vapor income and condensation is investigated, and two condensation stages are observed. The influences of surface wettability, porosity and thermal properties on condensation dynamics are also investigated. This presentation benefits improving the understanding of liquid-vapor phase change in porous media, as well as providing insights to corresponding engineering applications.
| Country | China |
|---|---|
| Acceptance of the Terms & Conditions | Click here to agree |
