Study on the improvement of flow characteristics for the optimal design of minimum flow valve with labyrinth channel

A connecting groove is added to the minimum flow valve with labyrinth channel as the optimized structure for flow field, and the internal flow characteristics of the valve are simulated by CFD method in a specific working condition. The result indicates that with the same pressure drop between the import and export, cavitation appears in the minimum flow valve under the specific working condition. But the value of minimum pressure is greater than that of the corresponding saturated vapor pressure all the time when a connecting groove is added. By comparison of the characteristic curves of the valve before and after adding a connecting groove, the flow coefficient of model with optimized structure is slightly greater than that of the original model. Meanwhile the resistance coefficient of the former is slightly less than that of the latter. In addition, the characteristics of the pressure and velocity distribution show advantages of the connecting groove in the matter of hydraulics.