Fault Diagnosis for Crankshaft Bearing in Diesel Engine Based on Bispectrum Analysis Fuzhou Feng, Aiwei Si* b , Pengcheng Jiang Department of Mechanical Engineering, Academy of Armored Force Engineering, No.21, Dujiakan District, Fentai area, Beijing 100072, China Military Transportation Department, Military Transportation University, No. 1, Dongjuzi District, Hedong area, Tianjin 300161, China...

The problem of air-fuel ratio (AFR) control of the port injection spark ignition (SI) engine is still of considerable importance because of stringent demands on emission control. In this paper, the static AFR calculation model based on in-cylinder pressure data and on the adaptive AFR control strategy is presented. The model utilises the intake manifold pressure, engine speed, total heat releas...

The simulation-based investigation of the variable displacement engine is motivated by a desire to enable unthrottled operation at part load, and hence eliminate pumping losses. The mechanism modeled in this work is derived from a Hefley engine concept. Other salient features of the proposed engine are turbocharging and cylinder deactivation. The cylinder deactivation combined with variable dis...

Silicon, the material of choice of the first (demonstration) microengine, exhibits strong thermal softening behavior at temperatures above 900 K. This thermal softening behavior limits the turbine inlet temperature, which in turn significantly degrades the overall engine efficiency. Previous studies have shown that hybrid structures of silicon and silicon carbide have good potential for improve...

Maximization of the fuel economy of the lean burn spark ignition (SI) engine strongly depends on precise air-fuel ratio control. A great challenge associated with the air-fuel ratio feedback control is the large variable time delay in the exhaust system. In this paper, a systematic development of an air-fuel ratio controller based on post lean NOx trap (LNT) oxygen sensor feedback using linear ...

Ñ State of the Art of Multi-Dimensional Modeling of Engine Reacting Flows Ñ An overview is provided of the state of art and future prospects for the use of CFD simulation in engine analysis and design. The aspects covered include geometry handling and mesh generation, numerical solvers, mathematical modeling of key physical phenomena, exploitation of parallel computers and industrial applicatio...

A new combustion model is developed and applied to simulate combustion in dual-fuel engines in which the premixed natural gas is ignited by the combustion flame initiated by a diesel spray. The model consists of a diesel auto-ignition model and a flame propagation model. A G-equation model previously developed to simulate SI engine combustion was incorporated with an auto-ignition model to simu...

The aim of this research is to study the influence of using ethanol-gasoline fuel blends on spark ignition engine performance characteristics and compare the obtained results with those using base gasoline. An electric generator operated by a SI (spark ignition, four stroke, single cylinder, air cooled) engine was used for conducting this study. The tested fuels were gasoline (E0) and gasoline-...

This paper presents a model of an electric variable valve timing (EVVT) system and its closed-loop control design with experimental validation. The studied EVVT uses a planetary gear system to control the engine cam timing. The main motivation of utilizing the EVVT system is its fast response time and the accurate timing control capability. This is critical for the combustion mode transition co...

The production of torque and pollutants of Variable Valve Actuation equipped internal combustion engines found in the automotive industry (both Diesel and gasoline engines) is studied. Variable Valve Actuation (VVA) is a technology which has been introduced to optimize engine efficiency at steady-states covering a wide range of operating conditions. In more details, the outcome of the internal ...