摘 要：为解决某电厂660 MW超临界循环流化床旋风分离器分级效率较低的问题，对旋风分离器排气管入口结构进行优化，将排气管入口改造成渐缩的锥体和渐扩的锥体。利用CFD软件，采用RSM湍流模型和DPM颗粒模型对传统与新型排气管结构的旋风分离器内部流场进行数值模拟，以旋风分离器的分级效率与阻力系数比值比较排气管入口结构的经济性。研究表明：与传统旋风分离器比较，正常运行时，渐缩结构的分级效率提高6.1%，但总压差增加108.83 Pa；渐扩结构的分级效率提高2.6%，总压差减小36.27 Pa；入口流速20 m/s时，渐缩结构旋风分离器最具经济性。

Abstract:In order to solve the problems that the cyclone separator of a 660 MW supercritical CFB boiler in a power plant has a relatively low gradation efficiency,optimized was the structure of the inlet of the exhaust gas pipe in the cyclone separator and reconstructed was the inlet in question to a converging and diverging cone.By making use of a CFD software,a RSM turbulent flow model and DPM particle model were adopted to conduct a numerical simulation of the flow field inside the cyclone separator with the structure of the traditional and novel exhaust gas pipe and the comprehensive evaluation factor Y=η/ζ (η denotes the gradation efficiency of the cyclone separator and ζ denotes the resistance factor of the cyclone separator) was introduced to compare the costeffectiveness of the structure of the inlet of the exhaust gas pipe.It has been found that compared with the traditional cyclone separators,when operating normally,the gradation efficiency of the separator with a converging structure can increase by 6.1%,however,the total pressure difference will increase 108.83 Pa while the gradation efficiency of the separator with a diverging structure will increase by 2.6% and the total pressure difference will decrease 36.27 Pa.when the flow speed at the inlet is 20 m/s,the value of the comprehensive evaluation factor of the separator with a diverging structure will be the highest and most economic.

TQ051.8