A Numerical Simulation of Water Strider Swimming on Water Surface using AMR Method

Abstract

The swimming of a water strider is a typical hydrodynamic phenomenon strongly governed by surface tension. In this study, we numerically studied the swimming dynamics of a water strider to elucidate the propulsion mechanism. To compute the interaction between its legs and the water surface, we performed gas-liquid two-phase flow simulation including the motion of moving objects using a weakly compressible scheme and a direct-forcing immersed boundary method. We also used a tree-based Adaptive Mesh Refinement (AMR) method for simulation to reduce computational load. Our simulation revealed that swimming propulsion arises from an imbalance of the capillary force.