Effects of modification on jet mixing of sword alternating lobed nozzle
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摘要: 结合现有交变波瓣喷管的特点对基准波瓣喷管进行处理,设计了一种新型交变波瓣喷管——剑形深波谷交变波瓣喷管.采用数值方法研究了扇形处理和斜切处理对剑形深波谷交变波瓣喷管射流掺混的作用.结果显示,随着扇形处理和斜切处理各自改型程度的增加,波峰尾流区掺混速度变快,而核心区主流完全掺混所需距离略有增加.斜切处理促进掺混能力优于扇形处理,扇形处理后引射能力和流动损失基本不变,斜切处理后引射能力和流动损失稍有减小.计算结果还表明流向涡的形态对掺混效率的影响大于流向涡的强弱.Abstract: A novel lobed nozzle named as sword alternating lobed nozzle was designed, combined with the characteristics of the existing alternating lobed nozzles to modify the baseline lobed nozzle. The effects of scalloping and scarfing on jet mixing of sword alternating lobed nozzle were investigated by numerical method. The results show that when the degree of scalloping or scarfing enhanced, the mixing in the downstream region of the lobe peak is accelerated, however the center primary flow needs a longish journey to be mixed. Scarfing has more capacity on promoting mixing than scalloping. Pumping performance and flow loss change little with scalloping whereas decrease slightly with scarfing. The results also indicate that the form of streamwise vortices has higher influence on mixing efficiency compared with the intensity of streamwise vortices.
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Key words:
- jet mixing /
- alternating lobes /
- scalloping /
- scarfing /
- numerical simulation
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