A Study on Combustion Parameters in an Automotive Turbocharged Diesel Engine

Giorgio Zamboni

doi:10.3390/en11102531

Abstract

A wide experimental database on indicated pressure diagrams measured on a turbocharged diesel engine, equipped with high and low pressure exhaust gas recirculation (EGR) circuits and a variable nozzle turbine (VNT), was processed to evaluate a large set of combustion parameters. Available data were referred to different tests in three part load operating conditions, focused on High Pressure EGR trade-off and the development of integrated control strategies for EGR and turbocharging systems aiming at NOX and fuel consumption reduction. According to their definition, combustion parameters were derived from pressure diagrams, its first derivative and heat release curves. Their calculation allowed enlarging the information content of measured in-cylinder pressure diagrams. Several linear correlations were then defined, linking engine operating, energy and environmental quantities to combustion parameters, useful for the analysis and modeling of in-cylinder processes and engine behavior. The influence of testing conditions on these relationships was also analyzed, referring to the investigated operating modes and the adoption of open and closed loop scheme for VNT management. Finally, general correlations were defined, linking NOX and soot emissions to selected quantities.

Highlights

Starting with the investigations of Rassweiler and Withrow in the 1930s [1], measurement of indicated pressure diagrams has been developed to become a robust technique for the development and control of internal combustion engines
The application of suitable processing procedures leads to the evaluation of rate of heat release (ROHR) curves [2,3], increasing the information derived from experimental observations to deepen the knowledge on combustion process
From a which started from an overview of general point of view, this is the main conclusion of this study, which general point of view, this is the main conclusion of this study, which started from an overview of literature to define a wide set of combustion parameters derived from from curves curves of of in-cylinder in-cylinder pressure, pressure, literature to define a wide set of combustion parameters derived from curves of in-cylinder pressure, its first derivative and heat release

Summary

Introduction

Starting with the investigations of Rassweiler and Withrow in the 1930s [1], measurement of indicated pressure diagrams has been developed to become a robust technique for the development and control of internal combustion engines. The influence of alternative fuels on combustion process can be supported by the analysis of pressure diagrams and related quantities. In [4], two blends of canola oil and hazelnut soapstock were tested in a single cylinder direct injection diesel engine. Canola oil was investigated in [5], where an extended comparison of pressure and heat release curves is presented, to outline the differences when using diesel oil, a B20 blend and neat canola oil. Due to the oxygen content in the canola oil, a shorter ignition delay was observed

Objectives

Methods

Discussion

Conclusion