针对由轴系扭转共振引起的车内噪声问题,提出加装多级扭振减振器来降低车内噪声的新思路.车内噪声试验表明,加装扭振减振器使得车内噪声可降低5dB,说明加装扭振减振器的措施对车内噪声控制是有效的.推导了所有级数多级减振器通用的动力放大系数表达式,采用序列二次规划(SQP)方法对并联和串联方式的1-10级减振器进行了参数优化,并对优化结果进行了对比分析.分析表明,不增加总惯量比情况下,并联和串联级数小于3时,能够通过增加级数获得较好的减振效果收益,串联2级和3级是较理想的多级减振器选择,为工程实践中多级减振器级数的选择提供了理论依据.
For the problem of automobile interior noise caused by driveline torsional resonance, a new idea of controlling the interior noise by installing a multi-degree of freedom(multi-DOF) torsional vibration absorber was proposed and experimented. The experimental results show that the interior noise is reduced by more than 5 dB when a multi-DOF torsional vibration absorber is installed, indicating that this measure for reducing the interior noise is effective. The universal dynamic magnification factor expressions of the multi- DOF torsional absorber with any degree of freedom were derived. The parameters of the absorber in parallel or series with the degree of freedom from one to ten were optimized and compared using the SQP method based on the derived expressions. The analysis shows that a better damping effect can be obtained by increasing the degree of freedom under the conditions that the sum of the ratios of inertias is kept same and the degree of freedom is less than three. This provides a theoretical basis for the choosing of the degree of freedom for such absorber in practice.