In this paper, the pipeline with guide vanes was taken as the research object, the flow noise was studied based on the hybrid calculation method, then the acoustic-structure coupling method was introduced to study the vibration and radiation noise, and then explored the best position of the guide vanes. Based on the pipeline experimental platform and improved experimental methods, it was found that the guide vanes had a better noise reduction effect on the elbows; based on that, a simulation study was carried out on the elbow with guide vanes, and the mechanism of the guide vanes on the velocity field and pulsating pressure of the pipeline was explored. Finally, the noise reduction effect at different positions of the guide vanes under different flow speeds was studied. The results indicated that the guide vane at the middle of the elbow had the best effect on improving the flow field and reducing noise in the working conditions studied in this article, providing a calculation basis for the design of the guide vane.

This paper investigates the vibro-acoustic behavior of composite sandwich panels with different cellular sandwich cores. In these designs, two face sheets are made of carbon/glass hybrid fiber bonded to the hexagonal honeycombs or chiral structure, and the filler is thermoplastic vulcanized rubber. Numerical simulation and model experiments are performed to obtain the vibration and sound radiation of composite sandwich panels with and without rubber. It is found that numerical results including vibration acceleration and sound pressure agree well with the corresponding experimental results. The analysis shows that the rubber filler is able to effectively reduce the vibro-acoustic response of composite sandwich panels. The effect of cellular sandwich core parameters on the vibration and sound radiation of composite sandwich panels is also discussed, which proves that the chiral structure can present superior dynamic properties.