Ball valve is an important control component in the pipeline transportation system. It is widely used in pipeline transportation systems to control the pressure and flow parameters of the conveying medium. Based on the user-defined UDF technology and the standard k-$\epsilon$ turbulence model using computational fluid dynamics techniques, the transient numerical simulation of the internal flow field of the ball valve under the variable speed law and different opening degrees is carried out, and the flow coefficient characteristics, resistance coefficient characteristics, inlet and outlet pressure drop, and internal flow field distribution of the ball valve are analyzed and studied. The results show that by designing the curve function of the ball valve actuator movement process with different structure forms, different types of ball valve flow coefficient and resistance coefficient curve can be obtained, which makes the ball valve as a flow regulating valve more widely used; Modifying the motion law of ball valve electric actuator has little influence on the distribution of ball valve flow field. As long as the motion law of ball valve actuator is optimized within a reasonable range, the purpose of pipeline flow control can be achieved, the inconvenience of valve replacement can be reduced, and the economic cost can be saved.

球阀是管道输送系统中重要的控制元件。广泛应用于管道输送系统中，控制输送介质的压力和流量参数。基于用户自定义UDF技术和标准k-$\epsilon$湍流模型采用计算流体动力学技术，对变速规律和不同开度下的球阀内部流场进行瞬态数值模拟，得到流量系数特性、阻力系数特性、进出口压降、并对球阀内部流场分布进行了分析研究。结果表明，通过设计不同结构形式的球阀执行机构运动过程的曲线函数，可以获得不同类型的球阀流量系数和阻力系数曲线，使得球阀作为流量调节阀的应用更加广泛；修改球阀电动执行器的运动规律对球阀流场分布影响不大。