基于混合FE-SEA法的镁质油底壳隔声数值优化

摘要

Analyzing the transmission loss of three kinds of oil pan which were steel,aluminum alloy and magnesium alloy by u-sing hybrid FE-SEA method.Considering the requirements of lightweight and the reduction noise,therefore,proposing the concept of noise reduction efficiency which was considered as evaluation index and the result showed that the complex performance of magnesium alloy oil pan was most advantageous.Analyzing the modal contribution of sound insulation trough and finding the key participation modal further improved the sound insulation of magnesium alloy oil pan.The serious vibration region which the inner surface added some stiffener was identified by extracting the velocity vibration type at the trough.This could effectively control the vibration and improved the sound insulation.%用混合FE-SEA法分析相同厚度的钢、铝合金和镁合金三种材质油底壳的隔声量，综合考虑轻量化和降噪的要求，提出降噪效率的概念，将其作为评价指标，结果显示镁质油底壳的综合性能最为优越。为了更进一步改善镁质油底壳的隔声效果，对隔声低谷处的模态贡献量进行分析，找出隔声低谷的关键参与模态。通过调取该频率处的速度振型，识别出油底壳上严重振动区域，在此区域内表面添加加强筋，有效地抑制了振动，同时低谷处的隔声也得到明显的改善。