고속 열유체 저어널 베어링에서 단일유체로서의 다등급 엔진 오일과 그 첨가액체들의 혼합물에 대한 성능 비교

Abstract

Dept. of Automotive Engineering, Hoseo University(Received February 7, 2012; Revised March 4, 2012; Accepted March 5, 2012)Abstract − To product multi-grade oil like engine oil, a sort of mineral base oil is mixed with a fundamentaladditive liquid package and a polymer liquid as viscosity index improver in order to improve the lubricatingproperty of oil. That is, engine oil is the mixture of more than two fluids. In this paper, it will be systematicallyorganized the governing equation describing non-Newtonian thermo-hydrodynamic lubrication related with themixture of incompressible fluids based on the principle of continuum mechanics. Then, in order to find howthe thermal analysis effect on the bearing performance lubricated with the mixture of multi-fluids, it will becompared to the performances between the mixture of each liquid to be blended and multi-grade engine oil asa single fluid in a high speed journal bearing. It is found that, in the case of lower viscosity oil, the differenceof pressure distribution between the above two cases turns out to be existed, even if the load capacity is samelevel.Keywords − mixture of fluids(유체의 혼합물), homogenous liquid(균질액), mineral base oil(광유 기유),additive liquid package(첨가제용 액체 패키지), polymer liquid for viscosity index improver(점도지수개선용 중합액체), multi-grade engine oil(다등급 엔진오일), non-newtonian fluid(비-뉴톤 유체), high speedjournal bearing(고속 저어널 베어링), thermo-hydrodynamic lubrication(열유체윤활)