Analytically Predicating the Multi-Dimensional Accuracy of the Honed Engine Cylinder Bore

Abstract

The dimensional accuracy of engine cylinder bore at multiscale has a tremendous influence on engine performances including friction power loss, vibration, leak tightness between piston and cylinder, and wear resistance. Tremendous researches were devoted to predict the dimensional accuracies of the honed cylinder by means of analytical, experimental, and numerical simulation methods. The dimensional quality of the honed cylinder bore was usually determined by establishing the relationship between honing parameters and dimensional accuracies of the honed cylinder bore. However, most researches predicted dimensional accuracy at macroscale or surface texture at microscale, respectively. Few efforts were devoted to predict the dimensional quality of honed cylinder bore at both macroscale and microscale levels simultaneously. To explore a new understanding of the honing mechanism of the cylinder bore, a multiscale model is proposed to predict the dimensional accuracy and surface texture of cylinder bore generated from the honing process at the macroscale and microscale simultaneously. The model aims to integrate both microscale factors including honing stone abrasives distribution, abrasive wear process, previous cylinder surface topography, and macroscale factors including cylinder geometric features and honing head motion trajectory into a multiscale analytical analysis. A force matching method is adopted in the multiscale predictive model to determine the feed depth in the honing of the cylinder bore. Thus, the proposed multiscale analytical model possesses an excellent capacity to simultaneously predict the roundness and cylindricity of the honed cylinder bore, as well as the surface texture/roughness of the honed cylinder bore in terms of Abbott-Firestone curve. The simulated results also revealed that the material removal process is closely related to the initial shape deviations of the cylinder bore, which cannot be corrected, compensated, or eliminated by the subsequent honing process given the deviations are associated with wavelengths higher than 27 mm under the given honing condition.