In this review article, we discuss recent studies on drops and bubbles in Hele-Shaw cells, focusing on how scaling laws exhibit crossovers from the three-dimensional counterparts and focusing on topics in which viscosity plays an important role. By virtue of progresses in analytical theory and high-speed imaging, dynamics of drops and bubbles have actively been studied with the aid of scaling arguments. However, compared with three-dimensional problems, studies on the corresponding problems in Hele-Shaw cells are still limited. This review demonstrates that the effect of confinement in the Hele-Shaw cell introduces new physics allowing different scaling regimes to appear. For this purpose, we discuss various examples that are potentially important for industrial applications handling drops and bubbles in confined spaces by showing agreement between experiments and scaling theories. As a result, this review provides a collection of problems in hydrodynamics that may be analytically solved or that may be worth studying numerically in the near future.

在这篇综述文章中，我们讨论了有关Hele-Shaw细胞中液滴和气泡的最新研究，重点关注缩放定律如何显示与三维对应物的交叉，并关注粘度在其中起重要作用的主题。随着分析理论和高速成像技术的进步，借助定标参数，对液滴和气泡的动力学进行了积极的研究。但是，与三维问题相比，对Hele-Shaw细胞中相应问题的研究仍然有限。这项审查表明，限制在Hele-Shaw单元中的影响引入了新的物理学，从而允许出现不同的缩放方式。以此目的，我们通过展示实验和定标理论之间的一致性，讨论了各种示例，这些示例对处理狭窄空间中的液滴和气泡的工业应用具有潜在的重要性。因此，本综述提供了流体力学中的一系列问题，这些问题可以通过分析来解决，或者在不久的将来值得进行数值研究。