弯管二次流及电厂锅炉均流技术的研究进展

Advances in the Study of the Flow Equalization Technology for the Secondary Flow in Bends and Boilers in Power Plants

对弯管二次流的研究因弯管技术在各工程领域的广泛应用而得到了发展。本研究在总结国内外大量文献资料的基础上,首先对弯管二次流形成原因、流动特性及研究方法(实验研究法、数值分析法和计算流体动力学研究法)进行了综述;其次,分析了弯管二次流对电厂锅炉烟风系统及锅炉经济运行的影响;最后,总结了电厂锅炉送风系统和SCR反应器烟道内采用的弯管均流技术,并针对大尺寸弯管内高雷诺数湍流流动均流技术进一步研究进行了展望。

The secondary flow in a bend has been studied in depth due to a wide-ranging use of the bend technology in various engineering domains.Firstly,on the basis of a large quantity of literatures both at home and abroad being summarized,an overview was given of the causes for the formation of the secondary flow in a bend,and the flow characteristics and research methods( including the test method,numerical analysis method and CFD method).Secondly,the influence of the secondary flow in a bend on the flue gas and air system of a utility boiler and its economic operation was analyzed.Finally,the flow equalization technology for bends adopted in the air supply system in a utility boiler and in the flue gas duct of the SCR reactor was summarized and the prospects of the future studies in the high Reynolds number turbulent flow equalization technology in a large-sized bend were also given.