关键词: 喷水推进, 数值模拟, 进口流道, 伴随方法

Abstract: The intake duct is one of the main components of a waterjet, and the hydraulic loss in the intake duct is an important part of the total loss of the waterjet. The geometry structure of the intake duct induces non-uniform inflow of the propulsion pump, which has adverse effects on the hydraulic efficiency and dynamic excitation of the waterjet. The intake duct of the waterjet is numerically simulated by using the adjoint method, the flow equations are first solved in the forward direction, then followed by the reverse solution of the adjoint equations. The flow region most related to the inflow is obtained based on the field of the adjoint operator. The method to capture the inflow surface of the waterjet duct based on the adjoint method is then established and verified. The duct geometry is optimized through the adjoint method by taking the boundary of the intake duct as the design input variable and the non-uniformity of the outflow as the objective. After 8 iterations, the non-uniformity of the outflow relatively decreases 18.7%, which validates that the adjoint method can effectively optimize the geometry of the intake duct.

Key words: waterjet propulsion, numerical simulation, intake duct, adjoint method