内混式喷嘴流场的数值模拟研究  

The Numerical Simulation of Internal Mixing Nozzle Flow Field

作　　者：张琳[1] 王立坤[1] 薛磊[1] 王会强[1] 

机构地区：[1]常州大学机械工程学院,江苏常州213016

出　　处：《高校化学工程学报》2012年第6期959-963,共5页Journal of Chemical Engineering of Chinese Universities

基　　金：江苏省科技厅计划项目(BY2012102);江苏省政府留学奖学金资助(2010);国家发改委节能技术改造财政奖励项目(发改环资[2008]2386号)

摘　　要：喷嘴的结构对燃油锅炉、加热炉的燃烧效率有着至关重要的影响。为了进一步提高燃油锅炉、加热炉的燃烧效率，提出了一种内混式蒸汽雾化燃油喷嘴结构，介绍了内混式雾化喷嘴雾化工作原理。建立了内混式喷嘴物理模型，采用CFD软件对内混式喷嘴的流场进行了数值模拟，探讨了内混式喷嘴雾化室的长度、气液比对雾化粒径的影响规律：同时，对喷嘴下游不同截面的雾化粒径大小分布规律进行了研究；并将平均雾化粒径模拟结果与常规内混式喷嘴经验公式的计算结果进行了比较。研究结果表明：内混式喷嘴的混合室长度最佳值是70～80mm；随着气液比的增大雾化粒径减小；液体燃料第二次雾化主要发生在燃料离开喷嘴100mm之内：同时，研究结果表明新型的内混式喷嘴的雾化粒径小于常规的内混式喷嘴的雾化粒径。A new kind structure of internal mixing nozzle was put forward in order to improve the combustion efficiency of fuel boilers and furnaces. The working principle of the new kind structure of internal mixing nozzle was introduced. Meanwhile, CFD software was used to build the physical model and simulate the flow field of the internal mixing nozzle. The influences of mixing-room length of the internal mixing nozzle and gas to liquid ratio on spray particle size were discussed. The distribution law of spray particle size at different face positions behind the fuel nozzle was studied. The numerical simulation results of the average spray particle size for the new structure of internal mixing nozzle were compared with the calculation results of experience formula for the conventional mixing nozzle. The results show that the best length of the mixing-room of internal mixing nozzle is 70-80 mm and the spray particle size reduces with increasing of gas to liquid ratio. It was found that the secondary spraying of liquid fuel happens within the area of 100 mm apart from the nozzle. The spray particle size of the new structure internal mixing nozzle is smaller than that of traditional internal mixing nozzle.

关 键 词：内混式喷嘴 数值模拟流场特性 雾化粒径 节能 

分 类 号：TK223.23[动力工程及工程热物理—动力机械及工程]