Fluctuation of the liquid surface in a condenser evaporator is undesirable to the operation of an air plant. Such an ill behavior can be determined from a knowledge of the effect of submergence on the boiling heat transfer in a lunate narrow channel with different gap size. Developed is a liquid supplying technology by assuming that the mass flow flux of the liquid varies from submergence. When submergence is less than unity, the heat transfer flux apparently decreases. With fresh liquid supply at the mid...