针对某溢洪道挑流消能存在的问题，采用VOF方法、立方体网格和k-ε紊流模型对溢洪道整体水力特性进行了三维数值模拟，对挑射水流流态、水舌掺气、水垫塘底板压强、下游河道流速等方面进行了分析。将某溢洪道由原高低式挑流鼻坎修改为差动式后，增大了下泄水流入水范围，提高了挑流消能的消能效率，减小了水垫塘底板压强，降低了下游河道水流流速。优化方案数值模拟结果得到了模型试验结果的验证。

To solve problems in the energy dissipation in a spillway, the hydraulic characteristics of spillway overflow are studied numerically by using VOF (Volume of Fluid) method, cubical mesh and 3D k-ε  turbulence model. The hydraulic characteristics, including flow pattern of jet flow, nappe aeration, pressure intensities on the plunge pool slab, flow velocity in the downstream channel are summarized. Flip bucket of the spillway is optimized by changing the original upper-lower flip bucket to differential flip bucket. Consequently, the flow pattern of nappe and efficiency of energy dissipation are improved, and the pressure intensity on the plunge pool slab and the flow velocity in the downstream channel are reduced. The numerical results of optimized scheme are verified by physical model test results.