阻尼力

The generalized force consists of the generalized conservative force, the generalized dissipation force and the generalized force in correspondence with the generalized coordinate except the generalized conservative force and the generalized dissipation force.

基于非自治有阻尼系统推导了第二类Lagrange方程，使用虚功原理，给出了广义力的求解方法，广义力由广义保守力、广义耗散力、除广义保守力和广义耗散力以外的对应于广义坐标的广义力这3部分组成。

In chapter 3, this paper describes the various models of the passive dampers for analysis and calculation taking account into the precision and other aspects, and points out the Maxwell model is enough to limn the characteristic of the fluid viscous damper under stress in most operating condition; in chapter 4, this chapter. further validates the rationality and advantage employing the fluid viscous damper in practical project and the reliability of the adopted model on the base of referring relevant experiments overseas and their data.

在文章的第三章，着重讨论了基于精确度等方面考虑而建立的被动阻尼器的各种受力分析计算模型，并指出Maxwell模型足以描述在大多数工况下粘滞阻尼器的受力特性；第四章则是在参考了国外的相关实验及其数据基础上进一步验证了工程上使用粘滞阻尼器的的合理性和优越性及分析计算模型的可靠性。

The fluid film bearing-flexible rotor nonlinear system with squeeze film damper is modeled practically using the finite element method and the Hamilton principle.(3) The film forces produced by fluid film bearing and squeeze film damper are determined by finite element method at any moment, and the Jacobian matrix is also determined.(4) A method for analyzing the dynamics of a large system with local nonlinearities is presented. The stability and bifurcation of the equilibrium position and the unbalance responce of a fluid film bearing-flexible rotor system with squeeze film damper are investigated based on the assumption of an incompressible lubricant together with the long bearing approximation for fluid film bearing, short bearing approximation for squeeze film damper and the"π"film cavitation model.

主要研究内容包括下面几个方面：（1）对挤压油膜阻尼器-滑动轴承-转子非线性动力系统中的非线性现象进行了机理方面的研究；（2）应用有限元方法及Hamilton原理对复杂的挤压油膜阻尼器-滑动轴承-转子非线性动力系统进行了建模分析；（3）对滑动轴承及挤压油膜阻尼器中任一时刻的油膜力及相应的Ja-cobi矩阵的确定进行了分析；（4）对一类具有局部非线性的多自由度动力系统，提出了一种可以有效地分析其动力特性的方法；（5）采用实验与理论分析相结合的方法，对挤压油膜阻尼器-滑动轴承-转子非线性动力系统的动力特性进行了分析。

Based on the concept of the non-proportional damping which may be divided into the proportional part for dissipation of energy and the nonproportional part for transformation of energy, a new modal superposition pseudo-force method is presented if the approximate decoupling method is not suitable. In this method the coupled modal equations are solved by iteration in which the coupling terms are treated as pseudo-force and set to the right side of the equations.

在不能进行近似解耦分析时，基于非比例阻尼可分为耗散能量的比例部分和转换能量的非比例部分这种概念，建立了一种拟力实模态叠加法，即把正则化的耦合模态方程中代表非比例阻尼部分的耦合项作为虚力，放到方程的右端，再运用迭代法求解。

Also the response amplitude will be changed with the initial conditions due to the nonlinear properties of the cables.Taking the bending stiffness, cable sag and cable inclination into consideration, the space vibration control of the cables using the visco-elastic dampers in cable-stayed bridges is investigated by joining the center difference method and the state space strategy. Both the maximum modal damping ration and the optimal damper size are obtained, then the practical suggestions are proposed for the design of the dampers. The space nonlinear vibration equations of the cable-damper system are derived, and anew hybrid method for solving the cable-damper system is presented by combing the Newmark method and Pseudo-force technology. According to the known properties of the cable-damper system, the nonlinear transient responses are analyzed under all kinds of excitations. Based on the transient response, the control effectiveness of the visco-elastic dampers is further demonstrated.

综合考虑了拉索抗弯刚度、垂度的影响，研究了粘弹性阻尼器对斜拉桥拉索的空间振动控制，联合中心差分方法及状态空间法，得出了拉索面内、外振动各阶模态可能达到的最大阻尼比及相应的最优阻尼器系数，并对斜拉桥拉索的阻尼器设计提出了参考建议：考虑拉索抗弯刚度、垂度及几何非线性，导出了索-阻尼器系统的空间振动非线性方程组，结合Newmark方法及伪力(Pseudo-Force)方法，创新地提出了求解非线性方程组的杂交方法，根据拉索-阻尼器系统的阻尼特性，在各种荷载作用下，对索-阻尼器系统的非线性瞬态振动响应进行了研究，从系统响应的角度更加直接地验证了阻尼器的控制效果。

The operating case of current liquid dampers, in which have been used in engineering, has been investigated by analyzing the distribution of oil kinetics parameters such as pressures and flow velocities based on finite element method for design of constructer of the new MR fluid damper and its characteristic simulation.

通过分析目前工程中的轿车液力阻尼器工作原理，采用有限元法对阻尼器内部流体的工作状态进行了分析；探讨了油液在工作过程中的压力、流速及其流场分布的动力学特征，为流体阻尼器结构设计及其阻尼特性的数值模拟分析提供了理论依据。

By means of simulink of Matlab, it is known that the method that electric field is strengthened and two damp holes are turned on can lead to transfer ratio of force to be fallen during the phase of low frequency; on the other hand, the method that electric field is weakened and two damp holes are turned off can lead to transfer ratio of force to be fallen during the phase of high frequency.

通过Matlab仿真计算可知，振动物体在低频阶段，加大电场和开启两阻尼孔能使力传递率较低；而在高频时，关闭电场和阻尼孔，其力传递率较小。

In this way, the hysteretic loop curve is not only related to the backbone curve, which is the fact in Masing's model, but also related to the damping ratio curve, so that the shear stress strain behavior under cyclic loads exhibits the actual damping characteristics of the soil.

本文提出了一种基于阻尼构造粘土恢复力模型的方法，使得由此构造的滞回曲线不但与土的骨架曲线相关，而且与阻尼比曲线有关，滞回圈的形状特性反应了土体的真实阻尼特性。

Finally, the wave equation of the electromagnetic field of this kind damper isderived from the Maxwells equation. The magnetic flux density at the boundary isassumed to be harmonic, so the analytical result of the wave equation is solved. When therotor rotates, eddy currents flowing inside the conducting material field are caused. Thetangential force acting on the rotor because of the action between eddy currents andmagnetic field is produced. The tangential force causes a retardation torque, which leadsto the increase of power and heating effects.

最后，应用Ahrens的电磁轴承简化模型，从Maxwell方程出发推导了应用于本文所述的被动式电磁阻尼器的波动方程，并用傅立叶级数把矩形磁场展开的谐变磁场作为磁场的边界条件，通过求解波动方程得到磁场的解析解，从而计算了阻尼器对转子的电磁力和由涡流引起的切向力产生的阻尼器附加功耗。

Nantong City of Spring giant hanger Limited, the company from 1985, I began specializing in the production of domestic and foreign variety of variable spring hanger, Constant Spring hanger, variable disc spring hanger, Constant disc spring hanger , Hydraulic dampers, dampers, shock absorber spring, the folder, connections, supports, pipe-hanger (including non-standard pieces of the design and manufacturing), the products are suitable for nuclear power plants, thermal power plants, boilers Industry, petrochemical enterprises.

南通市巨力弹簧吊架有限公司，我公司从1985年开始专业生产国内、国外各种规格的可变弹簧吊架、恒力弹簧吊架、可变碟簧吊架、恒力碟簧吊架、液压阻尼器、阻尼器、弹簧减振器、管夹、连接件、支座、管道支吊架（包括非标件的设计及制造），产品适用于核电厂、火力发电厂、锅炉行业、石油化工企业。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

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如果有任何问题，你可以随时联系我。