Down to the roughness scale assessment of piston-ring/liner contacts

Author(s)

Checo, H. M. ; Jaramillo, A. ; Ausas, R. F. ; Jai, M. ; Buscaglia, G. C. ; Ripa, M ; Ripeanu, RG ; Cicone, T

• Document type: Journal article
• Source: 9TH WORLD CONGRESS ON COMPUTATIONAL MECHANICS AND 4TH ASIAN PACIFIC CONGRESS ON COMPUTATIONAL MECHANICS; v. 174, p. 10-pg., 2017-01-01.

Abstract

The effects of surface roughness in hydrodynamic bearings been accounted for through several approaches, the most widely used being averaging or stochastic techniques. With these the surface is not treated "as it is", but by means of an assumed probability distribution for the roughness. The so called direct, deterministic or measured-surface simulation) solve the lubrication problem with realistic surfaces down to the roughness scale. This leads to expensive computational problems. Most researchers have tackled this problem considering non-moving surfaces and neglecting the ring dynamics to reduce the computational burden. What is proposed here is to solve the fully-deterministic simulation both in space and in time, so that the actual movement of the surfaces and the rings dynamics are taken into account. This simulation is much more complex than previous ones, as it is intrinsically transient. The feasibility of these fully-deterministic simulations is illustrated two cases: fully deterministic simulation of liner surfaces with diverse finishings (honed and coated bores) with constant piston velocity and load on the ring and also in real engine conditions. (AU)

• FAPESP's process: 11/24147-5 - Advanced computational methods for the simulation of lubrified contacts
• Grantee: Hugo Marcial Checo Silva
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/19249-1 - Computational fluid dynamics of Complex Interfaces: applications to the study of emulsions and the Micromechanics of biological membranes
• Grantee: Roberto Federico Ausas
• Support Opportunities: Regular Research Grants