Air–water two-phase flow and heat transfer in a plate heat exchanger

A plate heat exchanger is tested under two-phase flow conditions by using an air/water mixture as the cold stream. Visual observations recorded by a high-speed video camera lead to the construction of a flow regime map. The heat transfer coefficient of the air/water stream is measured as a function of air and water superficial velocities. The flow regime with a gas-continuous phase covering the core of the channel and liquid flowing in the form of rivulets inside the furrows shows particularly favorable heat transfer characteristics.