摘要
以OB-84型动叶可调轴流风机为研究对象,采用大涡模拟和FW-H声学模型对锯齿尾缘动叶风机进行了数值模拟,探讨了不同锯齿长度的尾缘对风机气动噪声、压强脉动及性能的影响,并分析了其流场特征和降噪机理。结果表明:锯齿尾缘可明显降低风机的中低频段噪声和流道中气流的压强脉动强度,锯齿长度越大,其影响越明显;锯齿尾缘增强了尾流区的流动掺混,改变了动叶尾缘脱落涡结构,形成了2层整齐的"梳状"流向对涡,由此降低了风机的气动噪声;模型A、模型B和模型C均可以在设计流量或小流量下提高风机效率,以模型A提升最明显,但在大流量下性能均低于原风机。
Taking the variable-pitch axial-flow fan of OB-84 type as an object of study, large eddy simulation and FW-H acoustic model were used to study the areoacoustics and performance of the fan with serrated trailing edge blades, during which, the effects of serrated edges with different lengths on the following parameters were researched, such as the noise, pressure fluctuation and performance of the fan, while the internal flow field and noise reduction mechanism were analyzed. Results show that the serrated trailing edge could significantly reduce both the noise in the middle and low frequency bands and the intensity of airflow pressure fluctuation in the flow passage;the longer the serration is, the more obvious the effects will be. The serrated trailing edge enhances the flow mixing in the wake region and changes the shedding structure at the trailing edge, leading to the formation of a two-layered comb-like flow-oriented vortex, thereby reducing the noise of the fan. Models A, B and C could improve the efficiency of the fan at design or lower flow rates. Model A presents the most obvious improvement on the fan performance among the three models, whereas at higher flow rates, the fan performance is lower than that of the original for all the three models.
作者
叶学民
张锐星
张超
李春曦
YE Xuemin;ZHANG Ruixing;ZHANG Chao;LI Chunxi(Key Lab of Condition Monitoring and Control for Power Plant Equipment,North China Electric Power University,Baoding 071003,Hebei Province,China)
出处
《动力工程学报》
CAS
CSCD
北大核心
2020年第3期231-238,共8页
Journal of Chinese Society of Power Engineering
基金
国家自然科学基金资助项目(11602085)。
关键词
锯齿尾缘
动叶可调轴流风机
气动噪声
风机性能
serrated trailing edge
variable-pitch axial-flow fan
aerodynamic noise
fan performance
