油烟机壳体的振动响应优化设计

Optimization design of vibration response of range hood's shell

为了降低油烟机壳体振动产生的噪声,基于油烟机壳体有限元模型,计算壳体在电机激励下的振动响应。在此基础上,以壳体四个部分的厚度为设计变量,保持壳体质量不超过原壳体质量,以壳体上四个敏感点的质点振速峰值为目标函数,对其进行了优化设计研究。利用商业软件Nastran计算质点振速,基于DOE方法利用iSIGHT-FD对壳体厚度进行优化,得到了优化的结构厚度。优化后,设计域各点的质点振速峰值均有不同程度的降低,振动速度级降低最大值达到8.2dB。结果表明,在保持吸油烟机壳体质量不增加的情况下,通过改变壳体四个部分的厚度可以达到降低辐射噪声的效果。

For the purpose of reducing noise from the vibration of range hood＇s shell,its vibration response under the motor＇s excitation was calculated based on the finite element shell model.Then,the optimal geometric design of the structure was preformed taking the peak velocities of mass points at four sensitive nodes as the objective functions in which the thicknesses of the four parts were adopted as the designing variables,and the weight of the structure was kept not more than its original weight.The velocities calculated by using the commercial software Nastran and the design of experiment（DOE） method was utilized to obtain the optimized shell thickness.After optimization,the peak velocities in the designed area are decreased more or less and a maximum 8.2 dB reduction of vibration velocity level is achieved.The results show that the changes of the four parts thicknesses do reduce the radiating noise of the range hood at the condition of no increase of the shell＇s weight.