The paper is concerned with prediction of elastic contact and elastohydrodynamic film thickness in worm gears. Using the undeformed geometry of the gap between gear teeth in contact a three-dimensional elastic contact simulation technique has been developed for calculation of the true area of elastic contact under load relative to the wheel and worm surfaces. A parallel investigation of elastohydrodynamic lubrication effects has been carried out using a special non-Newtonian, thermal solver which takes account of the nonsymmetrical and spin aspects of worm contacts. An interesting feature of the results obtained is the discovery of regions of poor film forming due to entrainment failure at the edges of the contact.

Issue Section:
Technical Papers
Keywords:
hydrodynamics, mechanical contact, tribology, elasticity, modelling, lubrication, rolling friction, machine bearings
Topics:
Elastohydrodynamic lubrication, Film thickness, Geometry, Pressure, Simulation, Stress, Wheels, Worm gears, Lubricants, Kinematics, Temperature, Lubrication
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