Analysis of influencing factors and prediction of aeroacoustic noise induced by the cruise chimney exhaust pipeline

Objectives The study aims to analyze the influencing factors of the aeroacoustic noise of the cruise chimney exhaust pipeline and predict the noise of the open area of a domestic cruise ship.

Methods A hybrid approach combining Large Eddy Simulation and Lighthill Analogy is used to conduct a numerical simulation of the pipeline’s aeroacoustic noise under the actual working condition of the cruise ship. Through the research, the impact of inlet flow rate, outlet pressure, cross-section shape, and bending angle on the pipeline aerodynamic noise is studied. A real-size cruise chimney exhaust pipeline model is established to analyze the main noise sources of the cruise chimney exhaust pipeline and to predict the noise of the open area.

Results The study found that the larger the inlet velocity and the bending angle, the greater the pipeline’s aeroacoustic noise. Furthermore, the aeroacoustic noise of the pipe with zero pressure-outlet is greater than that with a non-zero pressure-outlet. The study also finds that the aeroacoustic noise of the rectangular cross-sectional pipe is marginally smaller than that of a circular one. In addition, the narrowband peak frequency decreases as the bending angle increases. Except for the chimney outlet, the noise in the open area is at a low level.

Conclusions The study is of significant reference value for the control of aeroacoustic noise of the chimney exhaust pipelines on the cruise ship and the improvement of passenger comfort in open areas.