The flow-induced motion(FIM)of an elastically mounted square-section cylinder is experimentally investigated over a wide range of Reynolds numbers(1.5×10^(4)<Re<7.0×10^(4)).A 14 mlong towing tank water...The flow-induced motion(FIM)of an elastically mounted square-section cylinder is experimentally investigated over a wide range of Reynolds numbers(1.5×10^(4)<Re<7.0×10^(4)).A 14 mlong towing tank water channel and a carrier are designed to facilitate the investigation of FIM at high velocities.The cylinder is limited to a transverse oscillation and is carried inside the water channel.The effect of cylinder orientation on FIM is studied by performing experiments for two angles of attack(45°and 0°).The experiments are performed for two different spring stiffness to consider the influence of the natural frequency on the response of the system.Since the water has been allowed to stay calm between the tests,experiments are conducted with zero disturbance of the fluid flow around the cylinder.The experimental setup has shown promising results for a circular cylinder in our previous studies.The results for the diamond cylinder(square-section cylinder with a 45°angle of attack)indicate that FIM only consists of vortex-induced vibration(VIV)and the oscillation in the upper branch occurs in a wider range of reduced velocities compared with the circular cylinder.It can be concluded that a diamond cylinder is a better option for having synchronization in a wider range of water velocities for the purpose of energy extraction in VIV-based ocean energy conversion devices.展开更多
文摘The flow-induced motion(FIM)of an elastically mounted square-section cylinder is experimentally investigated over a wide range of Reynolds numbers(1.5×10^(4)<Re<7.0×10^(4)).A 14 mlong towing tank water channel and a carrier are designed to facilitate the investigation of FIM at high velocities.The cylinder is limited to a transverse oscillation and is carried inside the water channel.The effect of cylinder orientation on FIM is studied by performing experiments for two angles of attack(45°and 0°).The experiments are performed for two different spring stiffness to consider the influence of the natural frequency on the response of the system.Since the water has been allowed to stay calm between the tests,experiments are conducted with zero disturbance of the fluid flow around the cylinder.The experimental setup has shown promising results for a circular cylinder in our previous studies.The results for the diamond cylinder(square-section cylinder with a 45°angle of attack)indicate that FIM only consists of vortex-induced vibration(VIV)and the oscillation in the upper branch occurs in a wider range of reduced velocities compared with the circular cylinder.It can be concluded that a diamond cylinder is a better option for having synchronization in a wider range of water velocities for the purpose of energy extraction in VIV-based ocean energy conversion devices.
