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Bubble evolution and shear thinning effect are main factors affecting lubrication behavior of bubbly oil. In this study, a thermohydrodynamic lubrication model for the bubbly oil considering the bubble evolution and the shear thinning effect was established based on the multiphase mixtures theory. The influence of bubble evolution and shear thinning effect on the static behavior of bubbly oil lubricated bearing was analyzed, and an experimental study was conducted to verify the model. The result shows that the bubble radius is mainly dependent on the liquid pressure; the bearing static behavior is affected by the bubble evolution through the interface effect; the shear thinning effect of the pure oil can be enhanced with regarding the bubble evolution effect. • A thermohydrodynamic lubrication model for the bubbly oil was established based on the multiphase mixtures theory. • Bubble evolution and shear thinning effect on the lubrication performance of bubbly oil is discovered. • The bubble evolution process can be calculated with using the thermohydrodynamic lubrication model established. • An in-depth physical research on the bubbly oil lubrication is conducted through a case study with using journal bearing. [ABSTRACT FROM AUTHOR]

A thermohydrodynamic cavitating flow lubrication model including effects of cavitation, inertia and turbulence for high speed water-lubricated spiral groove thrust bearing was established. The static characteristics of the water-lubricated spiral groove thrust bearing at high speed condition were investigated using this model. The numerical calculation results have shown that load carrying capacity and friction torque reduce due to inertia and cavitation in high speed condition, while that load carrying capacity and friction torque increase due to turbulence. The maximum temperature rise increases due to inertia effect, and reduces due to cavitation effect. In addition, the influence of inertia effect on the static characteristics of water-lubricated spiral groove thrust bearing was greater than the cavitation effect under high speed condition. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to study dynamic characteristics for high-speed water-lubricated spiral groove thrust bearing considering cavitating effect. A lubrication model was established with multiple gas-liquid interface effects, the evolution of bubble volume caused by breakage and coalescence of bubbles was quantitatively described using the population balance equation. Dynamic characteristics of the spiral groove thrust bearing (SGTB) were predicted. An experimental rig was developed to measure the dynamic coefficients of the SGTB. The result shows that, when spiral angle is in small range, direct stiffness coefficients of the SGTB with the cavitating effect are larger than those without cavitating effect. The cavitating effect has less influence on the damping coefficients than the stiffness coefficients. • The dynamic characteristics of high-speed water-lubricated SGTB considering cavitating effect is studied. • The hydrodynamic lubrication model of cavitating flow for the water-lubricated SGTB was established. • The cavitation effect on dynamic characteristics of water-lubricated SGTB is analyzed. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the static and dynamic characteristics of the high-speed water-lubricated spiral-groove thrust bearing (SGTB) considering cavitating and centrifugal effects. A turbulent flow lubrication model was established based on gas-liquid two phase flow, and the influence of cavitation and centrifugal force on the static and dynamic characteristics was analyzed for the SGTB. An experiment setup was developed to measure the static and dynamic characteristics of the SGTB. The result shows that the proposed model with cavitating and centrifugal effects is more accurate than that without those two effects, the effect of the cavitation and centrifugal force should be considered when the modified Reynolds number exceeds 0.3. • The static and dynamic characteristics of high-speed water-lubricated SGTB is studied. • A turbulent flow lubrication model for the SGTB is established based on gas-liquid two phase flow. • All the static parameters and the dynamic coefficients reduce with the effect of cavitation and centrifugal force. • The effect of cavitation and centrifugal force must be considered when the modified Reynolds number exceeds 0.3. [ABSTRACT FROM AUTHOR]