大型压裂泵车车架实验应变模态分析方法研究

为解决某大型压裂泵车作业过程中存在的振动异常现象问题,将应变响应的随机状态空间模态识别技术应用到整车振动分析中。开展了实验应变模态分析,建立了振动应变响应与车架振动特性之间的联系,提出了消除整车振动剧烈的方法。以泵车压裂作业下三缸泵振动为激振源,进行了该大型压裂泵车车架振动试验,得到了车架在实际约束下的前六阶模态频率。研究结果表明:利用应变响应的随机子空间法可以较好地识别出约束状态下车架的固有频率;车架在实际约束状态下低阶固有频率在1.79 Hz~32.1 Hz之间,该频率与三缸泵激振频率存在重合区,是引起整车振动异常的主要原因。

Strain modal analysis of large-scale fracturing pump truck frame

In order to solve the problem of abnormal vibration in large-scale fracturing pump truck,the stochastic subspace identification （SSI）modal of vibration strain response was investigated.After the analysis of experimental strain modal,the relationship between vibration strain response and frame＇s vibration characteristics was established.A method was presented to remove serious vibration of pump truck.Using triplex pump as the excitation source,the vibration of the frame was tested,the frame＇s first six order natural frequencies were identified by the strain modal analysis SSI.The results indicate that the strain modal analysis SSI can identify the frame＇s natural frequencies in original support boundary conditions.The frame＇s low order natural frequency of is between 1.79 Hz～32.1 Hz,which has overlap area with the triplex pump vibration frequency and cause the truck＇s abnormal vibration.