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Stribech curve
The document discusses the history and development of the Stribeck curve. It describes the contributions of early researchers like Hirn, Thurston, Beauchamp Tower, and Stribeck himself who divided the curve into different lubrication regimes. Later, Gümbel and Hersey plotted the curve against a dimensionless number and reached the same results independently. The Stribeck curve shows the relationship between coefficient of friction and a bearing number and how friction decreases with increasing speed or decreasing temperature, traversing the lubrication regimes.
Stribech curve
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- 2. History and Origin G.A. Hirn Thurston Beauchamp Tower Stribeck Gümbel Hersey
- 3. G.A. Hirn HydrodynamicLubrication was clearly studied by him and relation between COF and Pressure was clearly stated. Speed relation was also done but not in a proper way COF as V is doubled V >> Load Carrying Capacity
- 4. Thurston Variation ofCOF by load (Contact Pressure) and Temp. Although Speed factor was considered in study and data collected was put in the table form and not as a graph. No information about the transition of HDL and BL although data when plotted can be seen
- 6. Beauchamp Tower Withincreasing speed and load the friction from low to higher angular velocities is going through a minimum He failed to give reason for low COF
- 7. Stribeck Performed severalexperiments to understand the effect of COF, V and Pressure He also explained the regions of transition and divided his graph in different Lubrication regimes To understand the Pressure, Load and velocity combined effect on FFL we can use the knowledge of Reynold’s Equation
- 9. Gümbel and Hersey They used Stribeck curve and plotted against a Dimensionless number . Both of them worked separately and reached to same ν results. ν N/P : P(Load per unit projected area) μ n/p : p(Pressure)
- 10. Fun Fact AdolfMartens, Director of the MPA had already published similar curve 17 years before Stribeck .
- 11. Detailed Study ofStribeck Curve A curve between coefficient of friction and bearing number
- 13. T ↑ ν ↓ μ↓ T ↓
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