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1.
李晶 《唐山学院学报》2016,29(6):1-5,40
给出了横向磁场作用下矩形薄板的磁弹性振动方程,针对一边固定、三边简支的矩形薄板,通过位移模态展开,并利用Galerkin法得到两自由度内共振非线性振动微分方程组。算例分析中,利用数值方法得到了系统内共振时两阶模态的时间历程响应图和相平面图,并分别讨论了系统初值及磁场强度对系统振动的影响。结果表明,系统呈现明显的非线性内共振特征。  相似文献   

2.
基于麦克斯威尔方程,给出导电薄板的非线性磁弹性振动方程,以及磁场环境下的电动力学方程和电磁力表达式。在此基础上,应用伽辽金法导出相应的非线性振动微分方程组,研究横向恒定磁场中周期载荷作用下梁式薄板的稳定性问题。根据李雅普诺夫近似稳定性理论,对稳态解的稳定性进行分析,得到稳定性的判定条件。通过对算例特征值的求解对振动的稳定性进行分析。  相似文献   

3.
刘勇 《电大理工》2001,(4):44-45
对PD控制器作用下的磁力轴承转子的机电耦合振动系统进行了研究.将电压控制改为电流控制,并引入了非线性项,应用平均法研究了转子系统的非线性振动,给出了磁力轴承控制系统参数与转子振动之间的关系.  相似文献   

4.
研究圆形极板机电耦合系统的强非线性问题。按照弹性力学理论建立圆形极板机电耦合系统的动力学方程,并利用Galerkin方法将其转化为非线性振动方程,即杜芬-马修方程,有两个外激频率。将参数变换的思想应用到多尺度法中求得系统的参强联合共振的幅频响应曲线,分析了不同的参数对共振的影响。  相似文献   

5.
RLC电路弹簧耦合系统的非线性振动   总被引:3,自引:2,他引:3  
为研究RLC电路弹簧耦合系统的非线性振动,通过拉格朗日-麦克斯韦方程,建立了受到简谐激励作用具有平方非线性的RLC电路弹簧耦合系统的数学模型。应用非线性振动的多尺度法,得到一种内共振和一种双重共振的一次近似解,并进行数值分析。讨论了激励、调谐参数等对系统的影响。发现在内共振2ω≈21ω,双重共振2ω≈2ω1且Ω≈1ω两种情况下,系统具有丰富的动力学现象。  相似文献   

6.
RLC电路弹簧耦合系统动力稳定性分析   总被引:1,自引:0,他引:1  
应用拉格朗日-麦克斯韦方程,建立了受到简谐激励作用的RLC电路弹簧耦合系统的数学模型,该系统是具有平方非线性双自由度系统。应用线性振动理论进行求解,得到了典型的Mathieu方程,再应用非线性振动的Lindstedt—Poincare法对得到的Mathieu方程进行求解分析,并讨论了系统的稳定边界。运用Matlab软件进行数值运算,得到了便于工程应用的稳定边界曲线。  相似文献   

7.
应用弹性理论和Galerkin方法建立Winkler地基梁在温度场中受简谐激励作用的非线性动力方程,应用非线性振动的多尺度法,求得系统主参数共振的近似解。分析不同参数对主参数共振响应曲线的影响。  相似文献   

8.
选取电荷、广义位移为电路耦合机电系统的广义坐标,得到系统的动能、势能、电能及耗散函数。根据经典的拉格朗日-麦克斯韦方程建立数学模型,得到的振动方程是弱非线性Duffing方程。应用多尺度法求得系统的主共振的幅频响应方程,并进行了数值计算,分析了不同的参数对共振的影响。随着碳纳米梁长度和交流电压幅值的增大,振幅和共振区增大;随着碳纳米梁与固定极板间距和阻尼系数的增大,振幅和共振区减小。  相似文献   

9.
介绍了水轮机组发电机转子在转动过程中的三种偏心:静偏心、振动偏心和转动偏心,建立了转子在不平衡电磁力作用下的非线性振动微分方程。采用数值方法分析了转动偏心和静偏心对轴系电磁振动特性的影响,结果表明,这两种偏心与电磁力呈非线性关系,随着偏心的增大使不平衡磁拉力作用不断加强,机组的横向振动固有频率有所降低,转子和转轮的振幅不断增大,倍频共振时的振幅也显著加大,转子系统展现出非常复杂的非线性动力学特征。  相似文献   

10.
为实现对机电耦合振动的精准检测,开展数控机床进给系统机电耦合振动检测技术的研究。根据数控机床进给系统的特点与作业方式,结合多物理场耦合关系,建立多柔性体机电动力方程;基于动力学角度,设计传动结构的运动学函数,采用功率计算分析法,计算数控机床进给系统的作业效率,构建进给系统机电耦合传动模型;考虑到进给系统机电耦合振动具有非线性特点,为简化计算,以进给系统机电在运动中非线性动力学为基础,在只考虑系统作业中直流分量与基波分量的基础上,计算系统的负载运行,以此实现对机电耦合振动的检测。设计对比实验,实验结果证明:设计的方法实际应用效果良好,可以提高检测结果的可靠性,实现对机电耦合振动的高精度检测。  相似文献   

11.
利用电磁学理论建立了带电圆环点电荷系统振动方程,讨论了系统在不同条件下的稳定性,对非线性振动系统,利用Maple计算绘图,分别作出了回复力和能量随位移的变化曲线、相图,求出了非线性振动系统的周期.  相似文献   

12.
An analytical sandwich beam model for piezoelectric bender elements is derived based on the first-order shear deformation theory (FSDT), which assumes a single rotation angle for the whole cross-section and a quadratic distribution for coupled electric potential in piezoelectric layers. Shear coefficient is introduced to correct the effect of transverse shear strain on shear force and the electric displacement integration. Static and free vibration analyses of simply-supported bender elements are carried out for the sensor function. The results illustrate the high accuracy of the present model compared with the exact 2D solutions.  相似文献   

13.
In this paper, a dynamic model is established for a two-stage rotor system connected by a gear coupling and supported on ball bearings with squeeze film dampers (SFDs). The nonlinear dynamic behavior of the rotor system is studied under misalignment fault condition. The meshing force of the gear coupling is calculated considering the deformation of the tooth caused by torque transmission and dynamic vibration. The contact force between the ball and race is computed based on the Hertzian elastic contact deformation theory and the elastohydrodynamic lubrication theory. The supported force of SFD is simulated by integrating the pressure distribution derived from Reynolds’s equation. The equations of motion are rewritten in non-dimensional differential form, and the fourth-order Runge-Kutta method is employed to solve the nonlinear dynamic equilibrium equations iteratively. To verify the validity of the dynamic model and the correctness of the numerical solution method, the experimental power spectra of the rotor system under various misalignment degrees are compared with the analytical results. The effects of several important parameters, such as the lubrication of the ball bearing, the centralizing spring stiffness, the radial clearance of SFD, and the misalignment of gear coupling, on the dynamic characteristics of the rotor system are investigated and discussed mainly focusing on the system stability. The response spectra, bifurcation diagrams, and Pointcaré maps are analyzed accordingly. These parametric analyses are very helpful in the development of a high-speed rotor system and provide a theoretical reference for the vibration control and optimal design of rotating machinery.  相似文献   

14.
船舶板架结构除了受到自身重力和设备重力作用外,还受到激振力的作用。应用大型有限元软件ANSYS软件对部分船体板架在受设备激振力和不受设备激振力两种情况进行计算,并就计算结果进行对比分析。结果显示,往往被我们忽视的激振力对船舶板架结构强度的影响不容忽视。  相似文献   

15.
Nonlinear bending of cantilever incompressible poroelastic beams subjected to a uniform load is investigated with the constraint that fluid flow is only in the axial direction. The governing equations for large deflection of the poroelastic beam are derived from theory of incompressible saturated porous media. Then, nonlinear responses of a cantilever beam with impermeable fixed end and permeable free end are examined with the Galerkin truncation method. The deflections and bending moments of the poroelastie beam and the equivalent couples of the pore fluid pressures are shown in figures. The differences of the results between the large deflection and the small deflection theories are analyzed. It is shown that the results of the large deflection theory are smaller than those of the small deflection theory, and the time needed to approach their stationary states for the large deflection theory is shorter than that for the small deflection theory.  相似文献   

16.
以温度场中斜梁受简谐激励的非线性振动方程为基础,应用非线性振动的多尺度法,求得非线性振动系统1/2亚谐-主参数共振的一次近似解,并进行定常解稳定性分析和数值计算.分析了温度、激励、几何尺寸对1/2亚谐-主参数共振幅频响应曲线的影响.  相似文献   

17.
以温度场中斜梁受简谐激励的非线性振动方程为基础,应用非线性振动的多尺度法,求得非线性振动系统主参数共振的一次近似解,并进行定常解稳定性分析和数值计算;分析了温度、长度、面积、激励等参数对主参数共振幅频响应曲线的影响。数值结果表明,系统主参数共振的共振区很窄,随着温度和长度的减小,系统主参数共振的共振区增大。  相似文献   

18.
Published research is minimal on vibration characteristics of hermetically sealed electromagnetic relay (EMR) ex- posed to mechanical environment. The vibration characteristics of armature system, link contact system with electromagnetic system will cause EMR malfunction. The nonlinear dynamics model of armature systems was studied by considering electro- magnetic attraction force and opposite mechanical force in this paper. Angular displacements of armature under different sinu- soidal vibration conditions are solved in order to obtain the failure mode result from armature system. Vibration tests showed the presented analyzing method is suitable for EMR. The conclusions are instructive for increasing vibration resistance of armature systems of EMR, and are significant for reliability design of switch apparatus.  相似文献   

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