Combined experimental and simulative approach for friction loss optimization of DLC coated piston rings

Abstract Piston rings cause significant friction losses within internal combustion engines. Especially the first compression ring, which is pressed onto liner by high cylinder pressure, contributes significantly to total loss of piston assembly. The tribological behavior oil scraper ring mainly related pretensioning force and can lead even at low idle speed. Due this, there always a markable risk wear for contact surfaces cylinder. “Diamond-like carbon” coatings on surface prevent are able reduce in ring-liner-contact. purpose this work was investigate benefit coating-system ring. Experimental studies were carried out fired single-cylinder engine using Indicated Instantaneous Mean Effective Pressure-method (IIMEP) crank angle-resolved detection assembly’s force. To be determine component-related fractions quantify hydrodynamic asperity parts locally time dependent, an EHD/MBS model created AVL EXCITE simulative investigation performed. This simulation validated experimental provided detailed information about individual conditions gap height each group. combined approach measurement enabled prediction aspects performance parameter virtual test bed.