Numerical Investigation on Coal-fired Power Plant Flue Pipe With Ash Deposition

Large rectangular flue pipes installed in coal-fired power plants usually need inner supports to ensure their stability. The design and arrangement of inner supports in rectangular flue pipe before electrostatic precipitator have an impact on precipitator's effectiveness and lifespan. Currently, there are two schemes used for setting inner supports in China. One is National Standard Specification (NSS) and the other is an American Combustion Engineering company design criterion (CE). No work has been done on the comparison of these two types of inner supports, especially with consideration of ash deposition. In this paper, the effect of ash deposition on pressure drop and velocity distribution in practical production are carried out, which are adopted flue pipe's volume 1/8 and 1/16 as the ash layer. The numerical results show that the ash deposition volume have effect on pressure loss of the straight flue pipes. However, the effect depends on the inner supports' type.