3:30 PM - 5:00 PM
[AAS06-P08] Parameter dependency of flow around an obstacle placed in a rotating stratified flow
Keywords:Karman Vortex, Computational Fluid Dynamics
In this study, assuming a situation in which an obstacle is placed in a rotating stratified flow, numerical simulations were carried out to investigate the structure of the flow when the flow passes through the obstacle. An interesting example of such a flow is the Karman vortex observed behind Jeju Island in Korea.The existance of the Karman vortex street has been confirmed by satellite images of clouds, which form well above the island. This indicates that the influence of the island extends far above the island in determing the flow structure. Therefore, the effects of the Earth rotation and stratification are thought to play an important role. The imcompressible Navier-Stokes equation with the Coriolis force as an external force and the equation of continuity(the advection equation for density that expresses the incompressibility condition) were used as the basic equations. These basic equations were solved using the fractional step method. At this time, the advection term was approximated by the upstream finite difference method with third-order accuracy so that calculations can be stably performed even at high Reynolds numbers. A turbulence model was not used.
As described above, the flow is considered to be affected by the flow velocity, the magnitude of the Coriolis force, and the strength of the density stratification. Therefore, we systematically changed these governing parameters and examined their effects on the flow structure.
As described above, the flow is considered to be affected by the flow velocity, the magnitude of the Coriolis force, and the strength of the density stratification. Therefore, we systematically changed these governing parameters and examined their effects on the flow structure.