强旋-V型钝体组合燃烧装置绕流实验研究

In order to explore the effects of strongly swirling flow on the vortex shedding patterns around the V-type bluff body,the effects of the installation position of the swirler outlet in the combined flame stabilizer on the vortex shedding frequency and the wake flow field are studied by using the PIV velocimetry and the high frequency dynamic pressure sensor. Compared with the V-type bluff body without swirling flow,the experimental results show that the vortex shedding frequency can be decreased when swirling is added. With the installation position of the swirler outlet moves toward the outlet position of the blunt body,the shearing vortex shedding frequency of the V-type bluff body increases gradually. When the swirler outlet is located outside of the bluff body,the geometrical characteristics of the shear vortex will be destroyed,which will lead to the change of the vortex shedding mechanism. Moreover,when the swirling volume flow rate is controlled within a certain range(0~1m3/h),increasing the swirl flow rate can reduce the shedding frequency of the shearing vortex around the bluff body. Compared with the case of V-type bluff body without swirling flow,the largest drop of the St number,about 34.96%,occures in the case under the 1m3/h swirling volume flow rate condition when the swirler outlet is located 1 time of the opening diameter at the trailing edge in the bluff body. A certain range of swirl flow is also helpful to expand the recirculation zone. When the swirl flow rate is 0.5m3/h,the length of the recirculation zone reaches the maximum,which is about2.3 times of the opening diameter. However,when the swirling volume flow rate is beyond a certain range,the wake flow field becomes deterioration,which is possible to influence the flame stability of the combined flame stabilizer.