엔진오일에 물이 혼합될 때 터보챠져 저어널 베어링의 열유체윤활 해석

Abstract

Abstract : In this study, using the governing equation for thermohydrodyamic lubrication involving the homogeneous mixture of incompressible fluid derived by based on the principle of continuum mechanics, it is discussed the effects of water within engine oil on the performance of high speed journal bearing of a turbocharger. The governing equations are the general equations being able to be applied on the mixture of Newtonian fluid and non-Newtonian fluid. Here, the fluid viscosity index, n of power-law non-Newtonian fluid is supposed to be 1 for the application of the journal bearing in a turbocharger lubricated with the mixture of two Newtonian fluid, for example, water within engine oil. The results related with the bearing performance are shown that the bearing friction is to decrease and the side leakage and bearing load increase as increasing the water content in an engine oil. Key words : Mixture of two fluids( 두 유체의 혼합물), Thermohydrodynamic lubrication( 열유체윤활), Emulsion( 유상액), Homogeneous liquid(균질액)