Study on the dredging effect of jet disturbance on the open channel sediment

This paper focuses on the dredging effect of an environmental protection dredging device combining airtight cavity and air knife jet. By means of flume model test, the influence of jet disturbance on the start-up of open channel sediment is studied under the condition of non-stop water, and the relationship between jet velocity, jet angle and dredging effect is established. The experimental results show that when a 30 mm wide air knife is intersected and the jet angle is 0°～7°, the dredging area can reach 87.7%, and the dredging effect can be significantly improved. On this basis, combined with the calculation of sediment scouring model, the flow field and sediment distribution inside the dredging device are verified. Aiming at high efficiency and stability, the technical parameters such as jet velocity, jet angle and dredging efficiency are further defined. The research results can provide theoretical supplement for the study of the dredging effect of jet disturbance, and also provide technical support for the non-stop water dredging of large open channels such as the main channel of the middle route of the South-to-North Water Transfer Project.