Lubrication and Ventilation System of Modern Engines - Measurements, Calculations and Analysis

The main function of an engine's lubrication system is to supply the different engine components with sufficient oil under all operating conditions. The demand of modern engines regarding the necessary oil pressure and flow of the individual components is influenced by the engine speeds and the accelerations due to the vehicle driving conditions.

In addition to that, the lubrication system effects the following topics:

• The drive power of the oil pump which is influenced by the oil pump capacity, the oil pressure and mechanical losses of the oil pump.
• The oil mass which is supplied to the engine oil consumers and flows back via the oil return system to the crankcase and the oil pan. In the crankcase ventilation system, oil and gas have to be separated.
• The oil aeration due to the oil mass in the crankcase and the moving parts.
• The ventilation losses in the crankcase which are influenced by the axial ventilation areas and the moved oil mass.

In this paper the development procedure, the measurement techniques used and special devices for the analysis and optimization of the ventilation system will be presented and described.