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A Thermal Equilibrium Analysis of Line Contact Hydrodynamic Lubrication Considering the Influences of Reynolds Number, Load and Temperature.

Yu X, Sun Z, Huang R, Zhang Y, Huang Y - PLoS ONE (2015)

Bottom Line: These variations have caused some inconsistencies in the conclusions of different researchers regarding the relative contributions of these thermal effects.The results indicate that the contribution of each thermal effect sharply varies with the Reynolds number and temperature.Convective effect could be dominant under certain conditions.

View Article: PubMed Central - PubMed

Affiliation: Department of Energy Engineering, Zhejiang University, Hangzhou, 310027, China.

ABSTRACT
Thermal effects such as conduction, convection and viscous dissipation are important to lubrication performance, and they vary with the friction conditions. These variations have caused some inconsistencies in the conclusions of different researchers regarding the relative contributions of these thermal effects. To reveal the relationship between the contributions of the thermal effects and the friction conditions, a steady-state THD analysis model was presented. The results indicate that the contribution of each thermal effect sharply varies with the Reynolds number and temperature. Convective effect could be dominant under certain conditions. Additionally, the accuracy of some simplified methods of thermo-hydrodynamic analysis is further discussed.

No MeSH data available.


Schematic diagram of the simplified model.
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pone.0134806.g001: Schematic diagram of the simplified model.

Mentions: As shown in Fig 1, the simplified model has been used to study the thermal equilibrium of line contact hydrodynamic lubrication. The cylindrical surface can rotate around its geometric center, and its radius is 0.15 m (>>oil film thickness). The stationary block is fixed in the x axis and y axis directions, and it is pressed by a force F onto the rotating cylindrical surface in the z axis direction (along the oil film thickness direction). The oil is supplied from the left side. Because of the wedge-shaped structure and the relative motion of the metal surfaces, a stable hydrodynamic lubrication film can be formed. The linear speed of the cylindrical surface varies from 4.71 to 21.60 m/s, and the inlet oil temperature varies from 60 to 90°C. The block surface temperature varies from 60 to 100°C. The applied load F varies from 220 to 380 N. The nomenclature of symbols are listed in Table 1.


A Thermal Equilibrium Analysis of Line Contact Hydrodynamic Lubrication Considering the Influences of Reynolds Number, Load and Temperature.

Yu X, Sun Z, Huang R, Zhang Y, Huang Y - PLoS ONE (2015)

Schematic diagram of the simplified model.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4526673&req=5

pone.0134806.g001: Schematic diagram of the simplified model.
Mentions: As shown in Fig 1, the simplified model has been used to study the thermal equilibrium of line contact hydrodynamic lubrication. The cylindrical surface can rotate around its geometric center, and its radius is 0.15 m (>>oil film thickness). The stationary block is fixed in the x axis and y axis directions, and it is pressed by a force F onto the rotating cylindrical surface in the z axis direction (along the oil film thickness direction). The oil is supplied from the left side. Because of the wedge-shaped structure and the relative motion of the metal surfaces, a stable hydrodynamic lubrication film can be formed. The linear speed of the cylindrical surface varies from 4.71 to 21.60 m/s, and the inlet oil temperature varies from 60 to 90°C. The block surface temperature varies from 60 to 100°C. The applied load F varies from 220 to 380 N. The nomenclature of symbols are listed in Table 1.

Bottom Line: These variations have caused some inconsistencies in the conclusions of different researchers regarding the relative contributions of these thermal effects.The results indicate that the contribution of each thermal effect sharply varies with the Reynolds number and temperature.Convective effect could be dominant under certain conditions.

View Article: PubMed Central - PubMed

Affiliation: Department of Energy Engineering, Zhejiang University, Hangzhou, 310027, China.

ABSTRACT
Thermal effects such as conduction, convection and viscous dissipation are important to lubrication performance, and they vary with the friction conditions. These variations have caused some inconsistencies in the conclusions of different researchers regarding the relative contributions of these thermal effects. To reveal the relationship between the contributions of the thermal effects and the friction conditions, a steady-state THD analysis model was presented. The results indicate that the contribution of each thermal effect sharply varies with the Reynolds number and temperature. Convective effect could be dominant under certain conditions. Additionally, the accuracy of some simplified methods of thermo-hydrodynamic analysis is further discussed.

No MeSH data available.