Wake of two interacting circular cylinders: A review

The study of two cylinders in crossflow is of both fundamental and practical importance. There has been a surge in research interest in the last decade dedicated to this flow. Two reviews have been conducted on this topic by Zdravkovich (1977) and Sumner (2010), respectively. While the former was published more than 30 years ago, the latter is an excellent collection of past investigations. This paper provides a compendium of previous studies from a perspective distinct from both Zdravkovich (1977) and Sumner (2010). There is no doubt that the wake of two cylinders is highly complicated, depending on both centre-to-centre spacing and orientation of the two cylinders with respect to incident flow as well as Reynolds number. In this review, the full picture of the flow is provided in terms of a number of regimes. The physical aspects in each regime are discussed in detail, covering the flow structures, Strouhal numbers, fluid forces, heat and momentum transport characteristics, and Reynolds number effect.