경사면으로 전파하는 고립파와 수직 벽면 충돌 과정에서 갇힌 공기에 의한 벽면 압력 진동 해석

Abstract

A developed code based on the unified conservation laws for incompressible and compressible fluids is applied to analyze wall pressure oscillations caused by entrapped air during a collision between a solitary wave and a vertical wall. To validate the developed code for the interaction of wave and structure, the computed results are compared with reported experimental data for interactions between a solitary wave and a submerged rectangular structure. Good agreements are archived for the time histories of velocity components at measuring points, which are dominated by vortex shedding caused by horizontal velocity behind the submerged obstacle while a solitary wave passes through. The validated code is applied to simulate collision between a breaking solitary wave and a vertical wall. Solitary waves are generated using a piston-type wave maker at one end of the computational domain, and an inclined plane is located in front of a vertical wall at the other end of the domain to expedite wave breaking. Pressure fields around an entrapped air pocket are shown at each one millisecond during the air pocket pulsates. The variations in amplitude, period, and attenuation of wall pressure oscillations are analyzed according to the distance from a solitary wave to a vertical wall, at the moment the solitary wave breaks on a slope. It is observed that the maximum wall pressure occurs just before the pulsating air pocket is entrapped as the distance increases, and this tendency is found to be in agreement with the recently reported experimental results.