基于SEA的船舶螺旋桨横振传递路径分析及降噪研究

采用统计能量分析(Statistical Energy Analysis, SEA)对某船螺旋桨轴横振在到舱室中产生的噪声进行了仿真,在图论框架下将SEA系统等效为赋权有向图,求解中高频振动能量传到舱室的主要传递路径。使用偏离算法从赋权图中得到了500条传递权重最大的路径,从而确定螺旋桨振动传递到主机舱和集控室的主要路径。分析结果显示,螺旋桨横振激励主要通过二层甲板的与横舱壁的耦合传递到船首方向的舱室产生噪音,双层底和船壳对振动传递影响较小。在传递路径结构和耦合连接处采取的降噪措施可使集控室的噪声在各频段降低3 dB。

Statistical Energy Analysis Weighted Graph Method for Transmission Path Analysis of Ship Propeller Lateral Vibration

Based on Statistical Energy Analysis (SEA), ship cabin sound level induced by lateral vibration of propeller shaft was simulated on a partial cabin SEA model. Weighted digraph of the SEA system, which was used to solve the energy transmission of mid-high frequency problem, was established based on the vibro-acoustic transmission path definition in graph theory. Using derivation algorithm, 500 paths with maximum transmission weight were derived from the weighted digraph, so that determined the dominant paths of vibration energy transmitted to the main engine room and engine control room. The results shown that vibration transferred to cabins is mainly through tween deck and transverse bulkheads, yet the hull and double bottom has little effect on the vibration transmission. Noise control measures taken on pathways structures and couplings reduced the sound level of engine control room by 3 dB on the interested bands.