We experimentally, numerically, and theoretically investigate the dynamics of cavitation bubbles in viscous liquids in a tube during a transient process. In experiments, cavitation bubbles are generated by a modified tube-arrest setup, and the bubble evolution is captured with high-speed imaging. Numerical simulations using OpenFOAM are employed to validate our quasi-one-dimensional theoretical model, which effectively characterizes the bubble dynamics. We find that cavitation onset is minimally affected by the liquid viscosity. However, once cavitation occurs, various aspects of bubble dynamics, such as the maximum bubble length, bubble lifetime, collapse time, and collapse speed, are closely related to the liquid viscosity. We further establish that normalized bubble dynamics are solely determined by the combination of the Reynolds number and the Euler number. Moreover, we also propose a new dimensionless number, , to predict the maximum bubble length, a critical factor in determining the occurrence of liquid column separation.

中文翻译：

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管内粘性液体瞬态过程中空化气泡的动力学

我们通过实验、数值和理论研究瞬态过程中管中粘性液体中空化气泡的动力学。在实验中，空化气泡是通过改进的管阻滞装置产生的，并通过高速成像捕获气泡的演变。使用 OpenFOAM 进行数值模拟来验证我们的准一维理论模型，该模型有效地表征了气泡动力学。我们发现空化的发生受液体粘度的影响最小。然而，一旦发生空化，气泡动力学的各个方面，如最大气泡长度、气泡寿命、溃灭时间和溃灭速度，都与液体粘度密切相关。我们进一步确定，标准化气泡动力学仅由雷诺数和欧拉数的组合决定。此外，我们还提出了一个新的无量纲数 来预测最大气泡长度，这是确定液柱分离发生的关键因素。