首页   按字顺浏览 期刊浏览 卷期浏览 Vortex dynamics in jets from inclined nozzles
Vortex dynamics in jets from inclined nozzles

 

作者: D. R. Webster,   E. K. Longmire,  

 

期刊: Physics of Fluids  (AIP Available online 1997)
卷期: Volume 9, issue 3  

页码: 655-666

 

ISSN:1070-6631

 

年代: 1997

 

DOI:10.1063/1.869223

 

出版商: AIP

 

数据来源: AIP

 

摘要:

Experimental tests were performed on round jets exiting inclined nozzles at a Reynolds number of 9000. Both natural jets and jets forced with single frequencies corresponding toStD=0.25,0.5, 0.75, and 1.0 were examined. In the natural case, the nozzle incline caused a mild increase in the radial spreading in the plane of azimuthal symmetry. The forcing amplified the asymmetric radial spreading by altering the vortex structure. In general, the inclined vortex rings rolled up at an angle slightly smaller than the nozzle incline angle. As the rings moved downstream, they migrated away from the jet centerline and their incline angle increased. Vortex rings generated atStD=0.5did not pair because that Strouhal number was near the “preferred” mode. For nozzles with slight inclines, forcing at larger Strouhal numbers led to pairing nearx/D=2in order to achieve the “preferred” mode. For nozzles with larger inclines, the vortex cores broke down before pairing could occur. Forcing at a lower Strouhal number(StD=0.25)yielded ring formation atStD=0.5and subsequent pairing. Increasing the incline angle moved the pairing location closer to the nozzle lip. Also, the pairing process was found to depend on the nozzle incline angle. ©1997 American Institute of Physics.

 

点击下载:  PDF (369KB)



返 回