Influence of axial bearing dynamics on rotor vibrations: Transient analysis considering cavitation and coupling of axial and radial fluid films

轴向轴承动力学对转子振动的影响：考虑空化以及轴向和径向流体膜耦合的瞬态分析

• 批准号: 301932901
• 负责人: Professor Dr.-Ing. Elmar Woschke
• 金额: --
• 依托单位: Institut für Mechanik (IFME)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/301932901?language=en
• 关键词: Influence; axial; bearing; dynamics; rotor

In addition to the elastic and inertia properties of the rotor as well as the external loads, the vibration behaviour of rotor systems is mainly determined by the bearings. Due to the advantageous mechanical and thermal characteristics as well as the low cost, hydrodynamic bearing constructions are often used. On the one hand, this applies to the journal bearings, which dominantly influence the bending vibrations, and at the same time thrust bearings are used to account for axial loads. Due to their respective stiffness and damping parameters, both bearing types significantly contribute to the system behaviour, which has a drastic effect on the resulting vibrations and stability. Continuous advancements and increasing demands require an improved simulation quality of transient system behaviour, which is why detailed modelling of the system properties of the rotor system, bearings and their interactions are necessary.For transient studies, it is not adequately possible to use established steady-state solutions in the field of coupled rotor bearing simulation. While the solution of a non-linear equation system is sufficient for quasi-stationary considerations of the bearing situation, time integrations must be carried out for transient questions with respect to rotor dynamics. A correspondingly detailed consideration of the bearing makes the evaluation of the Reynolds differential equation necessary at each step of the time integration, taking into account the time-variant cavitation state. In the previous project, a modified cavitation algorithm was developed for journal and floating ring bearings based on Elrod’s approach, which is now to be transferred to thrust bearings. In this context, in addition to the simple thrust bearing, various other forms of construction occur, which can be divided into combi bearings (combined journal and thrust bearings), floating disc bearings and tilting pad bearings. Hydraulic couplings between axial and radial lubricating films as well as mechanical couplings to the components of the rotor bearing system under the influence of cavitation must be taken into account. The extended simulation model is intended to validly predict relevant vibration phenomena (subharmonic vibrations, backward whirl excitation by external loads, tilting pad flutter) concerning both frequency and amplitude.

除了转子的弹性和惯性特性以及外部载荷外，转子系统的振动行为主要由轴承决定。由于有利的机械和热特性以及低成本，流体动力轴承结构经常被使用。一方面，这适用于主要影响弯曲振动的轴颈轴承，同时推力轴承用于轴向载荷。由于它们各自的刚度和阻尼参数，两种轴承类型都对系统行为有很大的贡献，这对产生的振动和稳定性有很大的影响。随着技术的不断进步和需求的不断增加，对瞬态系统特性的仿真质量提出了更高的要求，这就是为什么需要对转子系统、轴承及其相互作用的系统特性进行详细建模的原因。对于瞬态研究，在耦合转子轴承仿真领域中使用已建立的稳态解是不可能的。虽然非线性方程组的解对于轴承情况的准静态考虑是足够的，但是对于转子动力学的瞬态问题，必须进行时间积分。对轴承的相应详细考虑使得在时间积分的每一步都需要对雷诺微分方程进行评估，同时考虑到随时间变化的空化状态。在以前的项目中，基于Elrod的方法为轴颈和浮环轴承开发了一种改进的气穴算法，现在将其转移到推力轴承。在这种情况下，除了简单的推力轴承外，还出现了各种其他形式的结构，可分为组合轴承（组合轴颈和推力轴承）、浮动盘轴承和可倾瓦轴承。必须考虑轴向和径向润滑膜之间的液压耦合以及在气穴影响下与转子轴承系统部件的机械耦合。扩展的仿真模型的目的是有效地预测相关的振动现象（亚谐波振动，反向涡激外部负载，可倾瓦颤振）的频率和振幅。

项目成果

Analysis of dynamical behaviour of full-floating disk thrust bearings

• DOI: 10.24425/bpasts.2021.139001
• 发表时间: 2023-11
• 期刊: Bulletin of the Polish Academy of Sciences Technical Sciences
• 作者: Otto-von-Guericke Institute of Mechanics Otto-von-Guericke Steffen NITZSCHKE Institute of Mechanics-Otto-von-Guericke-Institute-of-Mechanics-Steffen-of-2265771920;And Otto-von-Guericke University 39106 Otto-von-Gueric Christian ZIESE-And-Otto-von-Guericke-University-39106-Christian-2265771954;Germany Magdeburg Germany Elmar WOSCHKE Magdeburg-Germany-Magdeburg-Germany-Elmar-WOSCHKE-Magdeburg-2265771918

Transient Simulation of a Rotor Supported in Partially Filled Herringbone Grooved Journal Bearings Using the Narrow Groove Theory: Boundary Conditions

使用窄槽理论对部分填充人字形槽轴颈轴承支撑的转子进行瞬态仿真：边界条件

• DOI: 10.1007/978-3-030-46466-0_21
• 发表时间: 2021
• 作者: Steffen Nitzschke;Elmar Woschke;Christian Daniel;Thorsten Sporbeck
• 通讯作者: Thorsten Sporbeck