KEYWORDS

Automotive, Inertia Effects in Hydrodynamics, Non-Newtonian Effects in Hydrodynamics

TRANSIENT THERMOHYDRODYNAMIC BEHAVIOR OF A TURBOCHARGER THRUST BEARING

With engine downsizing, low fuel consumption and high performance being the current challenges of automotive industries, turbochargers technology has to live up to the highest expectations. One of them consists in analyzing the realistic behavior of a turbocharger bearing system during transient events like sudden load steps or exhaust gas pulsations of the engine. In steady state, the understanding of such phenomena can be limiting. This paper deals with the numerical resolution of a transient formulation of the problem. Two rheological laws accounting for shear-thinning and viscosity-temperature dependency are combined with the Modified Phan-Thien and Tanner (MPTT) model in a thermohydrodynamic analysis. Fluid inertia effects due to high rotating speeds are included. Results in terms of load capacity and power loss are compared with experimental data obtained on a thrust bearing rig. They demonstrate the importance and the limits of these effects under realistic operating conditions.

AUTHORS

B. Rémy, B. Bou-Saïd, LaMCoS UMR 5259, INSA Lyon, Villeurbanne, France and T. Lamquin, Honeywell Turbo Technologies, Thaon-les-Vosges, France