KSME International Journal

, Volume 14, Issue 7, pp 737–743 | Cite as

A study on the circumferential groove effects on the minimum oil film thickness in engine bearings

  • Myung-Rae Cho
  • Hung-Ju Shin
  • Dong-Chul Han
Materials & Fracture · Solids & Structures · Dynamics & Control · Production & Design


This paper presents the effects of circumferential groove on the minimum oil film thickness in engine bearings. The fluid film pressures are calculated by using the infinitely short bearing theory for the convenience of analysis. Journal locus analysis is performed by using the mobility method. A comparison of minimum oil film thickness of grooved and ungrooved bearing is presented. It is found that circumferential 360° groove only reduces the absolute magnitude of the oil film thickness, but 180° half groove affects the shape of film thickness curve and position of minimum oil film thickness.

Key Words

Groove Minimum Oil Film Thickness Engine Bearing Mobility Method 



Width of bearing [m]


Width of groove [m]


Clearance [m]


Bearing diameter [m]


Fluid film force [N]


Film thickness [m]


Mobility term


Fluid film pressure [N/m2]


Bearing radius [m]


Acting force [N]


Axial coordinate [m]




Attitude angle [rad]

Radial coordinate [rad]


Viscosity [Pa·s]


Angular velocity of bearing [rad/s]


Angular velocity of journal [rad/s]


Angular velocity of load [rad/s]

\(\bar \omega \)

\(\frac{1}{2}\left[ {1 + \frac{{\omega _b }}{{\omega _j }} - 2\frac{{\omega _L }}{{\omega _j }}} \right]\)


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Copyright information

© Korean Society of Mechanical Engineers 2000

Authors and Affiliations

  1. 1.Turbo & Power Machinery Research CenterSeoul National UniversitySeoulKorea
  2. 2.Graduate SchoolSeoul National UniversitySeoulKorea
  3. 3.Mechanical Design & Production EngineeringSeoul National UnivSeoulKorea

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