...
首页> 外文期刊>Experiments in Fluids: Experimental Methods and Their Applications to Fluid Flow >An experimental study on jets issuing from elliptic inclined nozzles
【24h】

An experimental study on jets issuing from elliptic inclined nozzles

机译:椭圆形倾斜喷嘴射流的实验研究

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       

摘要

This paper reports on an experimental flow visualisation and digital particle image velocimetry inves_tigation on forced jets exhausting from aspect ratio equal to three elliptic nozzles with exits inclined at 30° and 60°. Flow images show that shear layer instabilities and sub_sequent vortex roll-ups are formed parallel to the inclined nozzle exits at 30° incline and that rapid re-orientation of the vortex roll-ups occurs at 60° incline. Flow observations also show that strong axis-switching occurs in a non-inclined elliptic nozzle. However, 30° and 60° elliptic inclined nozzles produce significant distortions to and suppression of the axis-switching behaviour, respectively. As a result, flow stresses and turbulent kinetic energy distributions become increasingly asymmetric. Their coherency and magnitudes along the shorter nozzle lengths also vary significantly. This can be attributed to the dis_similar formations of vortex roll-ups and rib structures, as well as unequal mutual interactions between them as the incline-angle increases. Lastly, results also show that unlike circular inclined nozzles, elliptic inclined nozzles do not produce serpentine-shaped jet columns nor lead to significant lateral jet-spread at large incline-angles.
机译:本文报道了一个实验流动可视化和数字粒子图像测速研究,研究了长宽比等于三个椭圆形喷嘴,出口倾斜30°和60°的强制喷射。流动图像显示,剪切层的不稳定性和随后的涡旋卷起与倾斜的喷嘴出口在30°倾斜处平行形成,并且涡旋卷起在60°倾斜处快速重新定向。流动观察还表明,在不倾斜的椭圆形喷嘴中会发生强烈的轴切换。但是,30°和60°的椭圆形倾斜喷嘴分别会严重扭曲和抑制轴切换行为。结果,流动应力和湍动能分布变得越来越不对称。它们沿较短喷嘴长度的相干性和大小也有很大差异。这可以归因于涡旋卷起和肋结构的不相似形成,以及随着倾斜角度的增加,它们之间不平等的相互作用。最后,结果还表明,与圆形倾斜喷嘴不同,椭圆形倾斜喷嘴不会产生蛇形的射流柱,也不会导致大的倾斜角度产生明显的横向射流扩散。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号