A new approach to the simulation of the hydraulic valve lifter of a car engine

A 2-degree of freedom model of the hydraulic valve lifter of an internal combustion engine is investigated using different system parameters. The oil compressibility and bulk modulus are integrated into the model. System vibrations, friction forces between the parts, forces derived from the finger follower and cam system, and check valve criteria are considered within the model for the closest possible data to the real mechanism. The viscosity changes caused by the engine temperature changes, the spring constant variations resulting from the deformations and the plunger-body radial clearance changes have been investigated. Using different types of approaches, the solutions of the computer simulation are analyzed to achieve the best results.