同心分级旋流结构的动态响应特征

实验探索了LESS(low emissions with stirred swirls)燃烧室头部出口附近的固有流动特征,及其对外界激励的响应.实验结果表明:预燃级旋流区域存在着周期性流动结构,而主燃级出口区域没有周期性流动结构;当外界激励的频率与流动固有频率耦合时,会引起预燃级流场畸变,并导致周期性流动的流速振荡幅值急剧增大. 

Dynamic response characteristic of concentric stage swirling structure

The natural flow characteristics and their response to outer excitations of a LESS (low emissions with stirred swirls) combustor head exit was studied by experiment. Experimental results shows that periodical flow structures are in the pilot swirling flow zone, while absent in the main outlet zone;the flow distortion in the pilot flow zone will happen when outer excitation frequency coupled with natural flow frequency, and the velocity oscillation amplitude of periodical flow will increase dramatically.