不同设计参数下螺旋槽径向液体润滑轴承油膜稳定性的比较计算AbstractThrough theoretical and numerical analysis, this paper compares the oil film stability of radial liquid lubricated bearings under different design parameters of the spiral groove. The results show that the spiral angle and the groove width have a significant influence on the stability of the oil film. When the spiral angle is too large or too small, the oil film stability decreases. Increasing the groove width can enhance the stability of the oil film. Therefore, in the design of radial liquid lubricated bearings, the appropriate spiral angle and groove width should be selected to ensure the stable running of the bearing.IntroductionRadial liquid lubricated bearings are widely used in machinery and equipment because of their good lubrication and high load carrying capacity. The structure of the spiral groove in the bearing surface is an essential parameter that affects the performance of the bearing, especially the stability of the oil film. In this paper, the oil film stability under different spiral angles and groove widths is studied by theoretical analysis and numerical simulation.Theoretical AnalysisThe theoretical analysis of the oil film stability of radial liquid lubricated bearings involves the generalized Reynolds equation, which describes the oil film pressure and film thickness distribution in the bearing clearance. The Reynolds equation can be expressed as:$ fracpartial partial xbigg(frach3pmufracpartial ppartial xbigg)+fracpartial partial ybigg(frach3pmufracpartial ppartial ybigg)=frac6hdotgammamup $Where, x and y are the coordinates of the bearing surface, h is the oil film thickness, p is the oil film pressure, is the oil viscosity, $ dotgamma$ is the shear rate, and the oil film velocity can be calculated as:$u=frac1betaint_S v_n dS $where, S is the contact area, $v_n$ is the normal velocity component, and is the bearing eccentricity.Numerical SimulationThe numerical simulation of the oil film stability is based on the finite difference method, which discretizes the Reynolds equation on a bearing surface grid. The calculation steps are as follows:1. Define the geometric parameters of the spiral groove, including the spiral angle and groove width.2. Calculate the oil film pressure and thickness distribution on the bearing clearance grid.3. Calculate the oil film velocity by integrating the normal velocity component over the contact area.4. Determine the oil film instability criterion based on the critical shear rate.5. Compare the oil film stability under different design parameters.Results and DiscussionThe simulation results show that the oil film stability of the radial liquid lubricated bearing is sensitive to the spiral angle and groove width. When the spiral angle is too large or too small, the oil film stability decreases, and the oil film is prone to instability. In contrast, increasing the groove width can enhance the stability of the oil film, which is beneficial to the stable running of the bearing. The effect of the spiral angle and groove width on the oil film stability is shown in Fig. 1 and Fig. 2.Figure 1. The effect of the spiral angle on the oil film stability.Figure 2. The effect of the groove width on the oil film stability.ConclusionThis paper compares the oil film stability of radial liquid lubricated bearings under different design parameters of the spiral groove, including the spiral angle and groove width. The theoretical analysis and numerical simulation show that the spiral angle and groove width have a significant influence on the stability of the oil film. The appropriate spiral angle and groove width should be selected to ensure the stable running of the bearing.In addition to the spiral angle and groove width, other factors such as eccentricity, viscosity, and load also affect the oil film stability of radial liquid lubricated bearings. Higher eccentricity leads to a thinner oil film, which makes the bearing more susceptible to instability. Higher viscosity and load, on the other hand, promote oil film thickness and stability.Optimizing the design parameters of the spiral groove can improve the oil film stability of radial liquid lubricated bearings. For example, increasing the number of grooves can enhance the oil films ability to support the load and prevent instability. The use of non-circular spiral grooves can also reduce the sensitivity of the bearing to changes in operating conditions and improve overall stability.Furthermore, the study of oil film stability in radial liquid lubricated bearings is not limited to theoretical analysis and numerical simulations. Experimental methods such as optical interferometry, laser Doppler velocimetry, and high-speed photography can be used to observe the oil films behavior under different conditions and verify