Low-pressure twin-fluid atomization: Effect of mixing process on spray formation

详细信息    查看全文

• 作者：Matou&scaron ; Zaremba^a ; ^{zaremba@fme.vutbr.cz} ; Lukas Weiß ; ^b ; ^c ; Milan Malý ; ^a ; Michael Wensing^b ; ^c ; Jan Jedelský ; ^a ; Miroslav Jí ; cha^a
• 关键词：Low-pressure ; Atomization ; Twin-fluid ; Droplet dynamics ; Liquid breakup ; Back illumination
• 刊名：International Journal of Multiphase Flow
• 出版年：2017
• 出版时间：March 2017
• 年：2017
• 卷：89
• 期：Complete
• 页码：277-289
• 全文大小：6346 K
• 卷排序：89

文摘

The present work comparably examines four different twin-fluid atomizers operated under the same operating conditions. Spray formation was examined by several approaches. The internal flow pattern was estimated using a simplified analytical approach, and the results were supported by the observation of the liquid discharge in the near-nozzle region. A high-speed back illumination was used for visualisation of the primary breakup. In the region of fully developed spray, the dynamics of droplets was studied using a phase-Doppler analyser (PDA). The information obtained from all methods was then correlated. Results show that the spray formation process depends mainly on the internal design of twin-fluid atomizer at low gas to liquid ratios (GLR). The amount of gas influences the character of the internal two-phase flow, a mechanism of the liquid breakup, droplet dynamics and a resulting drop size distribution. Differences among the atomizers are reduced with the increase in GLR. Moreover, it was shown that a certain mixing process can inherently create the annular internal flow which generates a stable spray characterized by relatively low mean droplet size.