Abstract

The purpose of this study is to explore the transient hydrodynamic coupling mechanism for misaligned journal–thrust microgrooved coupled bearings (referred to as coupled bearings) considering the axial microvibration under water lubrication. In the present model, it is assumed that the misaligned coupled bearing performs a sinusoidal reciprocating micromotion along the axial direction. Based on the developed numerical model, the effects of the working conditions, including the frequency and amplitude of the microvibration, misalignment angle, journal bearing radial clearance, and thrust bearing geometric clearance, on the transient hydrodynamic performance of the coupled bearing are studied. The simulation results indicate that the axial microvibration generates a periodic fluctuation in the load capacity for both the journal and thrust bearings, and the load fluctuation of the journal bearing is generated from the transient hydrodynamics of the thrust bearing. In addition, the negative misalignment mode is beneficial to improve the load capacity of the coupled bearing. Parametric studies demonstrate that although the decreasing microvibration frequency weakens the load capacity of the coupled bearing, it decreases the hydrodynamic load fluctuation. They also reveal that the increasing misalignment angle leads to an increase in the load fluctuation, and it also improves the load capacity.

摘要

本研究的目的是探索考虑水润滑下轴向微振动的未对准轴颈推力微槽耦合轴承（简称耦合轴承）的瞬态流体动力耦合机制。在本模型中，假设未对准的联轴器沿轴向进行正弦往复微动。基于开发的数值模型，研究了工作条件对耦合轴承瞬态流体动力性能的影响，包括微振动的频率和幅度、不对中角、轴颈轴承径向游隙和推力轴承几何游隙。模拟结果表明，轴向微振动会导致轴颈轴承和推力轴承的负载能力发生周期性波动，轴颈轴承的载荷波动是由推力轴承的瞬态流体动力学产生的。此外，负错位模式有利于提高联轴器的承载能力。参数研究表明，虽然降低微振动频率削弱了耦合轴承的承载能力，但它减少了流体动力载荷波动。他们还表明，增加的不对中角导致负载波动的增加，并且还提高了负载能力。参数研究表明，虽然降低微振动频率削弱了耦合轴承的承载能力，但它减少了流体动力载荷波动。他们还表明，增加的不对中角导致负载波动的增加，并且还提高了负载能力。参数研究表明，虽然降低微振动频率削弱了耦合轴承的承载能力，但它减少了流体动力载荷波动。他们还表明，增加的不对中角导致负载波动的增加，并且还提高了负载能力。