无霜冰箱风道的振动分析及改进

文章以无霜冰箱风道为研究对象，通过有限元模拟对风道固有频率、谐波响应和LMS Test.Lab振动试验进行分析，得到了风道壳体的固有频率、振幅极限和试验模态。计算结果表明，在风机工况状态下，风道振动噪声幅度最大时的频率是在风机工作的基频附近，通过风道粘贴阻尼的方式降低振幅，进而降低风道壳体传递给冰箱箱体的辐射噪声。试验结果表明：在风道壳体振幅最大的区域粘贴阻尼材料后，在半消声室进行噪声测试，冰箱整体减振效果明显且噪声级降低了1.9 dB。文章为风道减振降噪的改进提供方向和建议。

Vibration analysis and improvement of air duct of frost-free refrigerator

In this paper, the air duct of the frost-free refrigerator is taken as the research object. The natural frequency analysis, harmonic response analysis and LMS Test.Lab vibration test of the air duct are conducted by finite element simulation, and the natural frequency, amplitude limit and experimental mode of the air duct shell are obtained. The calculation results show that the frequency of the strongest vibration of air duct is close to the fundamental frequency of the fan, and the vibration amplitude can be reduced by pasting damping materials on the air duct, thereby the radiation noise transmitted from the duct shell to the refrigerator box is reduced. The experimental results show that after the damping materials are pasted on the area of the air duct shell with the largest vibration amplitude, the vibration of the whole refrigerator is obviously weakened and the radiated noise level is reduced by 1.9 dB according to the test in a semi-anechoic chamber. This paper provides a direction and suggestions for reducing vibration and noise in air duct.