The process of atomization often involves ejecting thin liquid sheets at high speeds from a nozzle that causes the sheet to flap violently and break-up into fine droplets. The flapping of the liquid sheet has long been attributed to sheet's interaction with the surrounding gas phase. Here, we present experimental evidence to the contrary and show that the flapping is caused by the thinning of the liquid sheet as it spreads out from the nozzle exit. The measured growth rates of the waves agree remarkably well with the predictions of a recent theory that accounts for sheet's thinning but ignores aerodynamic interactions. We anticipate these results to not only lead to more accurate predictions of the final drop-size distribution but also lead to more efficient designs of atomizers.

中文翻译：

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径向膨胀液体片的动力学

雾化过程通常涉及从喷嘴高速喷出稀薄的液体薄片，从而使薄片剧烈晃动并破碎成细小液滴。长期以来，液体薄片的拍打归因于薄片与周围气相的相互作用。在这里，我们提出相反的实验证据，并表明拍打是由液体薄板从喷嘴出口扩展而变薄引起的。测得的波浪生长速率与最近理论的预测非常吻合，该理论解释了薄板的变薄但忽略了空气动力学的相互作用。我们预计这些结果不仅将导致最终液滴尺寸分布的更准确预测，而且将导致雾化器的设计效率更高。