Abstract: Improving the body attachment dynamic stiffness is the main method to obtain excellent Noise,Vibration,Harshness experience. There are four method to calculate average dynamic stiffness, i.e. average method, index method, area method and 1/3 octave method. However, the meaning of four methods is not clear, and engineerings will be confused. In this article, the average dynamic stiffness is rewritten as a function of the dynamic stiffness of each frequency. The mathematical meaning of the average dynamic stiffness is given. Average method is arithmetic mean of dynamic stiffness curve. Index method is geometric average of dynamic stiffness curve. Area method is harmonic average of dynamic stiffness curve. 1/3 Octave method is square average of every dynamic stiffness curve. The body attachment average dynamic stiffness by calculated an example.

Key words: Dynamic stiffness; Average method; Index method; Area method; 1/3 Octave method; Post-processing method; Body attachment

摘要： 提升车身接附点动刚度是改善汽车噪声、振动与声振粗糙度性能的常用手段，现有四 种平均动刚度的求解方法（平均法、指数法、面积法、1/3 倍频程法）含义不清晰，不利于工 程区分。为明确四种平均动刚度含义，文章将平均动刚度改写为各频率动刚度的函数，通过 对比分析，提出各平均动刚度的数学含义，即平均法为动刚度曲线的算术平均，指数法为几 何平均，面积法为加权调和平均，1/3 倍频程法为分段平方平均。最后，通过实例计算车身接 附点平均动刚度，验证各后处理方法的差异。

关键词: 动刚度；平均法；指数法；面积法；1/3 倍频程法；后处理方法；车身接附点