Heat transfer coefficient correlation for two-phase flow in a vertical rectangular channel and Evaluation of pressure drop

Gas-liquid two-phase flow is an effective method of forced convection cooling inside pipes. This paper described the correlation formula that takes into account fluid temperature decrease due to evaporation and gas-liquid mixing, which is an advantage of two-phase flow in terms of heat transfer rate multiplication, and pressure drop, which is a disadvantage. Generally, causing poor heat transfer when at high liquid temperature, we conducted that situation. This cooling method is useful because the increase in heat transfer rate is greater than the increase in pressure drop.