The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJ...The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.展开更多
This paper presents an Operator -Splitting Method (OSM) for the solution of the universal Reynolds equation. Jakoobsson-Floberg-Olsson (JFO) pressure conditions were incorporated for the study of cavitation in a liqui...This paper presents an Operator -Splitting Method (OSM) for the solution of the universal Reynolds equation. Jakoobsson-Floberg-Olsson (JFO) pressure conditions were incorporated for the study of cavitation in a liquid-lubricated journal bearings. Shear flow component of the oil film was first solved by a modified upwind finite difference method. The solution of the pressure gradient flow component was completed by the Galerkin finite element method. Present OSM solutions for a slider bearing are in agreement with Elord's results. OSM was then applied to herringbone grooved journal bearing in this work. The film pressure, cavitation areas, load capacity and attitude angle were obtained with JFO pressure conditions. The calculated load capacities are in agreement with Hirs's experimental data. A comparison of the present results and those predicted by the Reynolds pressure conditions shows some differences. The numerical results indicate that the load capacity and the critical mass of journal (linear stability indicator) are higher, and the attitude angle is lower than those predicted by Reynolds pressure conditions in cases of high eccentricities.展开更多
基金supported by the Open Fund of Science and Technology on Thermal Energy and Power Laboratory(Grant No. TPL 2019B03)。
文摘The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.
文摘This paper presents an Operator -Splitting Method (OSM) for the solution of the universal Reynolds equation. Jakoobsson-Floberg-Olsson (JFO) pressure conditions were incorporated for the study of cavitation in a liquid-lubricated journal bearings. Shear flow component of the oil film was first solved by a modified upwind finite difference method. The solution of the pressure gradient flow component was completed by the Galerkin finite element method. Present OSM solutions for a slider bearing are in agreement with Elord's results. OSM was then applied to herringbone grooved journal bearing in this work. The film pressure, cavitation areas, load capacity and attitude angle were obtained with JFO pressure conditions. The calculated load capacities are in agreement with Hirs's experimental data. A comparison of the present results and those predicted by the Reynolds pressure conditions shows some differences. The numerical results indicate that the load capacity and the critical mass of journal (linear stability indicator) are higher, and the attitude angle is lower than those predicted by Reynolds pressure conditions in cases of high eccentricities.
