This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Three-Dimensional Multiphase Physics-Based Modeling Methodology to Study Engine Cylinder-kit Assembly Tribology and Design Considerations- Part I
ISSN: 0148-7191, e-ISSN: 2688-3627
To be published on September 15, 2020 by SAE International in United States
Understanding cylinder-kit tribology is pivotal to durability, emission management, reduced oil consumption and efficiency of the internal combustion engine. This work addresses the understanding of the fundamental aspects of oil transport and combustion gas flow in cylinder kit using simulation tools and high-performance computing. A dynamic three-dimensional multiphase, multicomponent modeling methodology is demonstrated to study cylinder-kit assembly tribology during the four-stroke cycle of a piston engine. The percentage of oil and gas transported through different regions of the piston ring pack is estimated and the mechanisms behind this transport are analyzed. The velocity field shows substantial circumferential flow in the piston ring pack leading to high-velocity blowback into the combustion chamber during the expansion stroke. Oil initialization and management of a continuous supply of oil throughout the cycle are observed to govern how much oil would be lost to the crankcase and combustion chamber. The calculated blowby results agree with the results of a quasi-one-dimensional cylinder kit analysis system of programs known as CASE (Cylinder-kit Analysis System for Engines). Implementing this three-dimensional methodology leads to a better understanding of cylinder-kit fluid flow physics. The findings presented in this work paves the way to further the ongoing development effort of optimum cylinder-kit designs with controlled gas leakage, low oil consumption and promoting designs with low cylinder-kit friction.