To study the unstable water surface near an aqueduct and to provide eliminating measures in a water conservancy project, numerical simulations on flows around circular cylinders and gate piers in various channels, including straight channels with different width values, transition channels with gradient contraction sections and curved channels were performed under the condition of high Reynolds number ( Re =5×106) through COMSOL Multiphysics software. The influences of channel layout and blunt body shape on the surrounding flow field morphology and forces acting on the structures were analyzed. The results show that, in the range of the calculation parameters, as the width of the straight channel decreases, the lift and drag coefficients of the cylinder increase with the blockage ratio. The gradient section of transition channel has little effect on flow around a cylinder. For curved channels, a deflection coefficient is adopted to indicate the asymmetry flow distribution. In flow with a greater deflection coefficient, the structure may suffer lift and drag coefficients with greater asymmetry and larger average values. The results of flow around piers show that, the flow fields and force characteristics of piers without pier tail are similar with those of a cylinder. The increase of pier length can reduce the resistance coefficient. The lift and drag coefficients are greatly reduced by the streamlined body shape of piers with tails. Adding an appropriate pier tail is an effective measure to solve the vortex shedding for flow around a gate pier.