通过曲线拟合计算损耗因子

损耗因子是进行振动计算分析时必须输入的关键参数之一，直接影响振动计算和分析结果的准确性和可靠性。而传统的半功率带宽法和衰减法由于各自的局限性而无法得到理想的结果。该文将曲线拟合应用于时域衰减法测量损耗因子的数据处理中，通过理论分析、信号预处理、曲线拟合，准确地计算出激励频率下试件的损耗因子。通过与传统方法计算结果的比较，证明该方法在损耗因子小于0.01的小阻尼情况下具有精度更高、稳定性更好以及抗干扰能力更强的优点，可应用于损耗因子的衰减法测量中。

Loss factor calculation by curve-fitting

Loss factor is one of key parameters for vibration analysis, which can affect the precision and reli-ability of vibration calculation and analysis. It is very difficult to achieve the good results when using tradi-tional methods, such as half-power bandwidth method in frequency domain and decay method in time do-main, because of their limitations. In this paper, a new method using curve-fitting with more accurate and more stable compared to traditional methods is presented. The loss factors could be obtained accurately through pre-process and curve-fitting based on the decay measurement. The new method can be used in decay waveform measurement especially when loss factor is lower than 0.01.