基于FE-SEA混合模型的轿车车内噪声预测

摘要

For predicting in-car noise in intermediate frequency range, firstly the subsystems of car body are divided to build a hybrid FE-SEA model for car. Then by combining theory and test, the modal density and interior loss factor of car body structure as well as the radiation efficiency of body panels are obtained. And the excitation on engine mounts and the excitation of road to car body at connecting points between suspensions and car body are determined by theoretical calculation. Finally the noise at driver's right ear is predicted by using both hybrid FESEA model and SEA model respectively, which are then compared with test data. The results show that in the whole frequency range of 20 -1,000Hz, the noise predicted by hybrid FE-SEA model is much closer to test result than that by SEA model, in particular at medium frequency band.%为对轿车车内中频噪声进行预测,对轿车车身各子系统进行划分,建立了轿车整车混合FE-SEA模型;采用理论和试验相结合的方法求得车身结构的模态密度、内损耗因子和车身板件的辐射效率;采用理论计算方法确定发动机悬置点的激励和路面对车身在前后悬架与车身连接点处的激励.分别用施加激励后的混合FE-SEA模型和SEA模型预测驾驶员右耳旁的噪声,并与试验进行对比.结果表明:在200~1000Hz 整个频率范围内,FE-SEA混合模型的预测结果与试验数据吻合良好,明显优于SEA模型的预测结果,尤其足中频段.