Low-noise Design for Engine Oil Pan

The FE model for a cast aluminum?oil pan was built.The modals of free vibration,the surface vibration and radiation noise if the pan were calculated using the combination of FEM and BEM method.The surface vibration velocity and the total sound power level were obtained.Then,the side face of the oil pan was reinforced and the shape of its bottom was improved,and the levels of structure vibration and radiation noise of the oil pan were predicted.The results were compared with those of the original pan.It is found that after the improvement,the frequency of free vibration is greatly increased,the vibration mode also changes obviously,the vibration amplitude is decreased,and the total sound power level is reduced by 3.1 dB.