Professor Dowson's contribution to the bearing industry

Dowson’s film thickness relationship is used in the bearing industry and miscellaneous organizations (ISO, DIN, and FVA) for defining the Lamda ratio (film thickness/roughness) or Kappa ratio (viscosity/reference viscosity) and corresponding lubrication factor affecting bearing life. The film thickness is also used for defining the rolling element–race shear rate, hence traction force, defining bearing torque and power losses. Traction forces can also explain rolling element acceleration, skidding, risk of cage failure, and smearing.