Modelling the hydrodynamic support of cylinder bore and piston rings with laser textured surfaces

An one-dimensional computer model was used to simulated surface texture effects on engine cylinder bore, top and oil control rings. Steady state, reciprocating tests and engine conditions were considered. For the engine simulation, conditions close to the top reversal and at mid-stroke were simulated. Different micro-dimple geometries were considered, as well as full and partial texturing. As main conclusion, micro-dimples on the bore and rings were able to generate significant hydrodynamic support with potential to reduce both friction and wear. A special benefit was predicted when the micro-dimples were on the flat surface of the oil control rings.