Three dimensional numerical simulation on bubble growth and merger in microchannel boiling flow

This paper presents a three dimensional direct simulation on boiling flow in a rectangular microchannel. A coupled volume-of-fluid and level-set method was adopted to track the liquid-vapor interface. An immersed boundary method was used to deal with the temperature around the interface. The numerical result was compared with a previous experimental result, and the outcomes matched. Growth and merger of the bubbles were simulated and the impact of the bubbles' merger on the heat transfer was analyzed. The results show that the merger can produce a temporal growth in heat flux, while the thin liquid film between the bubble and the wall holds the main reason for the high heat flux in microchannel boiling flow.