Study on structural response and noise characteristics of composite pump-jet propulsor

Objectives The composite material has the advantages of light weight, corrosion resistance and high damping ratio, which is of great significance to improve the comprehensive performance of pump-jet propulsor. Methods In this paper, combining Computational Fluid Dynamics and Finite Element Method, a two-way fluid-structure coupling method and a flow noise prediction method based on FW-H equation are established for the composite rotor pump-jet propulsor. Then investigated the open water performance, structural response characteristics and flow noise characteristics of the composite rotor pump-jet propulsor under different working conditions. Results Results show that with increase of advance speed coefficient, the structural deformation and stress-strain values of composite pump-jet propulsor rotor decrease, while the overall sound pressure level of flow noise decreases first and then increases, the lowest is 87.60 dB when J=0.8. Compared with the traditional aluminum alloy pump-jet propulsor, the rotor structure deformation of model scale composite pump-jet propulsor is little, which has no effect on its hydrodynamic shape and does not cause obvious change its hydrodynamic performance; the flow noise of composite pump-jet propulsor is reduced slightly at specific frequency, and overall sound pressure level reduction is also relatively small. Conclusion The application of composite material to the rotor structure design has achieved weight reduction, but has no great impact on the hydrodynamic performance and noise performance of pump jet propeller, which provides a theoretical basis for improving its comprehensive performance.