烟气中灰粒对锅炉过热器、省煤器传热影响的研究

Effect of Ash Particle in Flue Gases on Heat Transfer of Superheater and Economizers

采用模拟含尘烟气实验研究了烟气中含尘浓度、颗粒粒度和烟气速度等关键因素对锅炉过热器、省煤器传热的影响，得出了具有工程应用价值的经验关联式，并用于计算分析煤粉炉、两级分离的循环流化床锅炉和中温分离的循环流化床锅炉的过热器、省煤器等对流管束在考虑固体粒子影响作用后烟气侧的传热系数。通过传热机理分析，提出了可用于锅炉对流受热面设计的多相流传热模型，为循环流化床锅炉过热器和省煤器的设计计算提供了依据和方法。

Abstract The effects of vital factors on heat transfer in boiler superheaters and economizers, like dust concentration in flue gas, particle size and gas velocity has been experimentally studied with the help of dust laden simulated flue gas.Engineering applicable correlation formulas were obtained, which have been used to calculate and analyze the gas side heat transfer coefficients of superheaters and economizer convection tube banks of a pulverized coal boiler, a CFB boiler with two stage separation and those of a CFB boiler with the influence of the solid particles taken into consideration.After having performed an analytical study of the heat transfer mechanism,a multiphase heat transfer model is proposed which can be used for designing convection heating surfaces of boilers,thus providing basis and method for the calculation and design of superheaters and economizers of CFB boilers.