摘要
Object of the present work is to study the characteristics of the hydrodynamic forces on the circular cylinder near the plane wall at various distance in a steady flow. Experiments were conducted in the gravity-type water tunnel and maximum flow velocity was 1 m/sec. The hydrodynamic coefficients of the cylinder and the vortex shedding frequency were measured using a balance with water proof strain gauge in a water tunnel under the conditions of Reynolds number ranged from 4.54×103 to 1.76×105, gap-to-diameter ratio in O<G/D <3.0 and the boundary layer thickness on the plane wall at the station of the centre of the model being smaller than 0.10 D. The change of these coefficients with Re and G/D was found. The lift frequency shows that a strong non-linear coupling action appears when G/D reaches 0.5 and the vortex shedding is supperessed when G/D is 0.2.
Object of the present work is to study the characteristics of the hydrodynamic forces on the circular cylinder near the plane wall at various distance in a steady flow. Experiments were conducted in the gravity-type water tunnel and maximum flow velocity was 1 m/sec. The hydrodynamic coefficients of the cylinder and the vortex shedding frequency were measured using a balance with water proof strain gauge in a water tunnel under the conditions of Reynolds number ranged from 4.54×103 to 1.76×105, gap-to-diameter ratio in O<G/D <3.0 and the boundary layer thickness on the plane wall at the station of the centre of the model being smaller than 0.10 D. The change of these coefficients with Re and G/D was found. The lift frequency shows that a strong non-linear coupling action appears when G/D reaches 0.5 and the vortex shedding is supperessed when G/D is 0.2.
