On the Characteristic Surface of a Steam Boiler : 2nd Report, Effect of Boiler Pressure

Abstract

The lower the boiler pressure is, the larger the temperature difference between water tube and combustion gas becomes. Hence, the boiler proper absorbs larger heat energy in low pressure operation than that in high pressure operation. At the same time the quantity of heat transferred to economizer or air preheater decrease, because the outlet gas temperature at boiler proper becomes low. But boiler efficiency increase. Though we use same fuel in the boiler, the characteristic surface of a boiler is changed by the boiler pressure. In this paper, we study the relation between boiler pressure and efficiency.