This review focuses on direct numerical simulations (DNS) of turbulent flows laden with droplets or bubbles. DNS of these flows are more challenging than those of flows laden with solid particles due to the surface deformation in the former. The numerical methods discussed are classified by whether the initial diameter of the bubble/droplet is smaller or larger than the Kolmogorov length scale and whether the instantaneous surface deformation is fully resolved or obtained via a phenomenological model. Also discussed are numerical methods that account for the breakup of a single droplet or bubble, as well as multiple droplets or bubbles in canonical turbulent flows.

中文翻译：

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充满液滴或气泡的湍流的直接数值模拟

本综述重点关注充满液滴或气泡的湍流的直接数值模拟 (DNS)。由于前者的表面变形，这些流的 DNS 比载有固体颗粒的流更具挑战性。讨论的数值方法根据气泡/液滴的初始直径是否小于或大于 Kolmogorov 长度尺度以及瞬时表面变形是否完全解析或通过现象学模型获得进行分类。还讨论了解释单个液滴或气泡破裂的数值方法，以及规范湍流中的多个液滴或气泡。