Engineering Commons^™

Effect Of Cetane Number And Volatility On Autoignition And Combustion Of Alternative Fuels And Their Surrogates, Ziliang Zheng

Wayne State University Dissertations

Diesel engine has become a popular choice for trucks, trains, boats, and most other heavy-duty applications. The inherent benefits of diesel engine are high thermal efficiency and specific power output, but there is a concern about high levels of engine-out NOx and particulate matter emissions, which is a major contributor in environment pollution. Moreover, concern about the crisis of crude oil reserves, increasing gas price, trade deficit, and homeland security enhances the interests in alternative fuels.

Unlike conventional diesel fuel, alternative fuels have wide range of properties, such as volatility, cetane number, density, viscosity and lower heating value, which influence …

Effect Of Intake Temperature And Boost Pressure On The Auto-Ignition Of Fuels With Different Cetane Numbers And Volatilities, Chandrasekharan Jayakumar

Wayne State University Dissertations

The aim of this research is to investigate the effect of air inlet temperature and boost pressure on the auto-ignition of fuels that have different CNs and volatilities in a single cylinder diesel engine. The inlet air temperature is varied over a range of 30°C to 110°C at a constant intake pressure of 1.1 bar. The boost pressure is varied from 1.1 bar to 1.5 bar at a constant intake temperature of 60°C. All engine tests are run at steady-state conditions. The fuels used are ultra-low-sulfur-diesel (ULSD), JP-8 (two blends with CN 50 & 31) and F-T SPK. Detailed analysis …

Ionization In Diesel Combustion For On-Board Diagnostics And Engine Control, Tamer Hassan Badawy

Wayne State University Dissertations

Diesel engines have been known for their high thermal efficiency and specific power output, but there is concern about engine-out NOx and particulate matter emissions. To meet the current emission standards, advanced diesel engines are fitted with electronically controlled fuel injection systems and sophisticated and expensive after-treatment devices. Further improvements are still needed to meet future goals in better fuel economy and the more stringent emission standards. In order to meet these goals, there is a need for the control of the combustion process to reduce engine-out emissions in real-time and reduce the demand on the after-treatment devices. This requires …

Ionization In Diesel Combustion: Mechanism, New Instrumentation And Engine Applications, Fadi Estefanous

Wayne State University Dissertations

Diesel engines are known for their superior fuel economy and high power density. However they emit undesirable high levels of nitrogen oxide (NOx) and black particulate smoke (Soot). To reduce these emissions, close loop engine control strategies are required. Therefore, there is a need for an in-cylinder combustion sensor. The ion current sensor has been used for combustion sensing in gasoline engines for which ionization mechanisms have been developed. This is not the case in diesel engines.

In this dissertation, a new mechanism for ionization in diesel engines has been developed and experimentally validated. Moreover, a three dimensional model has …

Opposing Effects Of Recirculated Gases During Cranking On Cold Start Of Diesel Engines, Rafik N. Rofail

Wayne State University Dissertations

ABSTRACT

OPPOSING EFFECTS OF RECIRCULATED GASES DURING CRANKING ON COLD START OF DIESEL ENGINES

by

RAFIK ROFAIL

August 2011

Advisor: Dr. Naeim Henein

Major: Mechanical Engineering

Degree: Doctor of Philosophy

Enhancing cold start of DI diesel engines is the motivation behind this study. A new control strategy is proposed to reduce the cranking period and the white smoke emissions. In the strategy, the gases leaving the cylinder during the cranking period are recycled back into the intake manifold using two different methods. In the first method the engine-out gases during cranking are recirculated into the intake manifold and their rate …