ELASTOHYDRODYNAMIC PISTON SKIRT LUBRICATION- EFFECT ON TRIBOLOGICAL PERFORMANCES

model of elastohydrodynamic lubrication of piston skirt
is developed in this paper. The secondary motion of the piston,
the lubrication and the elastic deformations of skirt and
cylinder are described by a transient strongly nonlinear system
coming from the coupling of the dynamics equations of piston
secondary motion and the Reynolds equation. The iterative
Newton-Raphson method in conjunction with Murty’s
algorithm for cavitation was used to solve the problem. An
optimum skirt curved profile, which maintain piston in
optimum performance characteristics, is adopted. Using the
tribological performance of the lubricated skirt-cylinder, the
results - minimum oil-film thickness, maximum pressure in the
lubricant film and friction- are compared to the elastohydrodynamic solution and the rigid skirt-cylinder
solution. The effect of elastic deformation of both skirt and
cylinder show that elastohydrodynamic analysis is necessary
for an accurate prediction of a piston- cylinder performance.
The computational work, applied to a solid skirt piston of a V-8
direct injection diesel engine truck, should be a powerful design
analysis tool, which can be used to increase the available
engine power through optimum piston performance
characteristics.