BTA深孔加工镗杆的横向随机振动  

Lateral random vibration of boring bar for BTA deep-hole process

作　　者：赵武[1] 张全斌 李亚敏 荆双喜[1] ZHAO Wu;ZHANG Quanbin;LI Yamin;JING Shuangxi(School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo 454000,China;College of Mechanical and Electrical Engineering,Xinxiang University,Xinxiang 453003,China)

机构地区：[1]河南理工大学机械与动力工程学院,河南焦作454003 [2]新乡学院机电工程学院,河南新乡453003

出　　处：《振动与冲击》2024年第3期46-57,共12页Journal of Vibration and Shock

基　　金：国家自然科学基金面上项目(51075126);河南省科技攻关项目(192102210052,232102221017)。

摘　　要：采用随机方法分析了蕴含轴向流动流体的BTA(boring and trepanning association)深孔镗杆在随机力下的横向随机动力行为。建模时考察了流固耦合镗杆承受的弯曲、拉伸和扭转变形;经Galerkin Method离散化处理,分析了BTA镗杆在有、无随机激励两种情况的特征值和特征频率对振动特性的影响;利用响应方差最大值和谱密度解析了BTA镗杆横向振动的临界转速与临界失稳频率;明确了镗杆随转速、刚度、初始轴向总力和剪切模量等参数变化对系统振动特性的影响机制:镗杆转速变化对系统稳定性不再具有单调性,随BTA镗杆转速持续增加,系统可历经两次转速的临界失稳,相继出现二次失稳和二次稳定;增加系统等效刚度和等效剪切模量会促进工作过程的稳定,改变轴向力对工作过程稳定的影响不明显;并以随机振动物理试验信号的功率谱分析,验证了理论仿真结果与试验结果的一致性。该研究在一定程度上揭示了BTA深孔工艺系统运动状态的复杂性,这种研究模式为进一步分析在复杂状态下的运动演化提供了更多的可能。研究结论为更好地理解BTA深孔镗杆工作时的随机动力行为提供了依据,也为BTA深孔工艺过程的振动控制和参数优化奠定了理论基础。Here,the random method was used to analyze lateral random dynamic behavior of a BTA deep hole boring bar containing axially flowing fluid under random force.In modeling process,bending,tensile and torsion deformations of fluid-solid interaction boring bar were investigated.After discretization processing using Galerkin method,effects of eigenvalues and characteristic frequencies of BTA boring bar on its vibration characteristics were analyzed with and without random excitation.Critical rotating speed and critical instability frequency of lateral vibration of BTA boring bar were solved analytically using the maximum response variance and spectral density.The influence mechanism of boring bar on vibration characteristics of the system with changes of parameters of rotating speed,stiffness,initial axial total force and shear modulus was clarified.It was shown that variation of boring bar rotating speed no longer has monotonicity on the system stability,with increase in BTA boring bar rotating speed,the system rotating speed can undergo two critical instabilities,i.e.,2 instabilities and 2 stabilities occur crosswise one after another;increase in system equivalent stiffness and equivalent shear modulus can promote the stability of working process,while changing axial force has no obvious impact on the stability of working process;the consistency between theoretical simulation results and test results was verified through power spectral analysis of random vibration experimental signals;this study to some extent reveals the complexity of motion state of BTA deep hole process system to provide more possibilities for further analyzing motion evolution under complex states;the study conclusions can provide a basis for a better understanding of random dynamic behavior of BTA deep hole boring bar during operation,and also lay a theoretical foundation for vibration control and parametric optimization of BTA deep hole process.

关 键 词：BTA深孔镗杆 横向振动 随机振动特性 特征值 响应方差 谱密度 

分 类 号：O324[理学—一般力学与力学基础] TB123[理学—力学]