Student Posters Repository

Cacti and succulents have shallow root systems but still can withstand high winds in their natural environment without being uprooted or damaged. Previous experimental and numerical studies showed the ability of grooved cylinders, which mimic cactus shapes, to decrease the drag coefficient and reduce lift force fluctuations over a range of Reynolds numbers. Most of these studies were inspired by the Saguaro cactus, which is native to Mexican and South-Western American deserts, and typically has 10-30 ribs. However, there are a number of cacti and succulents that have only three or four ribs. The aim of this project is to use computational fluid dynamics to study the aerodynamics of cylindrical structures with a low number of ribs. Preliminary 2D URANS simulations were performed and showed that drag coefficient and lift force fluctuations are strongly dependant on the orientation of the cactus-shaped cylinder with respect to the incoming flow. In the next stage scale resolved (Large Eddy and Detached Eddy) simulations will be performed on regional HPC facilities to give insight into 3D flow features around cactus-shaped cylinders with four ribs. In addition, flow statistics will be compared to previous results for the smooth cylinder and cylinders with many ribs.