A systematic approach to analyze and improve surface features of powertrain components

Many internal combustion engine (ICE) failures are related to sealing systems such as cylinder head gasket and excessive wear between cylinder walls and pistons. The investigations of the root causes of such failures are heavily dependent on experiments and forensic analysis. This heuristic process is time consuming and not cost-effective.;In this dissertation, mathematical models and optimization techniques were systematically structured in order to virtually evaluate the sealing performance between the cylinder deck face and the head, and the wear mechanism between the cylinder wall and the piston. Analytical models for evaluating the flatness of the cylinder deck face and cylinder bore distortion were developed, in which the effect of both operating and machining loads on the deck face and cylinder bore surface characteristics were considered. A unique method for milling and boring force evaluation and manufacturing process optimization was proposed. All methods developed in this research, including the cylinder bore distortion analysis, deck face flatness evaluation and manufacturing process optimization can help IC engine structure design to be more robust, efficient and reliable, particularly at the conceptual design stage.;In addition to application in the conceptual design, the methodology developed in this dissertation can also be used for engines in production to investigate and evaluate cylinder bore distortions and the deck face flatness under both operating and machining loads. The manufacturing processes for the cylinder bore boring and deck face milling can be optimized by applying the methodology proposed in this dissertation. Although the methodology was developed to analyze and evaluate the cylinder bore distortion and cylinder deck face flatness and related machining operation processes, it can be widely applied to conduct design and process substantiation for any cylindrical and flat surface generations in the nature of proximity.;Keywords: Internal Combustion Engine (ICE), Computer Aided Engineering (CAE), Surface Distortion/Error Analysis, Cylinder Bore Distortion, Flatness, Circularity (roundness), Cylindricity, Manufacturing Process, Finite Element Analysis (FEA), Kinematic Simulation in Machining Process (KSMP), Manufacturing Process Simulation, Numerical Method.