Engineering Commons^™

An Experimental Study Of Fuel Selection For A Gasoline Multi-Mode, Spark Ignited – Compression Ignition Engine, Zachary J. Stanchina

Dissertations, Master's Theses and Master's Reports

In this study of fuels of different reactivities and their performance in a low-temperature combustion (LTC) engine. The engine was a 2.2L CRDI engine code D4HB provided by industry partner Hyundai America Technical Center inc. (HATCI). The engine was instrumented with in-cylinder pressure sensors allowing for monitoring of the combustion process.

First, the engine was operated with standard US pump grade gasoline, Research Octane number (RON) 91 E10, to find initial operation conditions as well as control points of stable operation for daily checks on system conditions.

Tested were 8 different fuel blends, the four base blends were provided by …

Partially Stratified Combustion Of Natural Gas For Spark Ignition Engines, Philip S. Zoldak

Dissertations, Master's Theses and Master's Reports

In this work, the advantages of partially stratified direct injection natural gas versus premixed port-fueled injection natural gas spark ignited engines has been studied. The volumetric efficiency, ratio of specific heats and turbulent kinetic energy was found to be higher with direct injection versus port-fueled injection thus improving thermal efficiency. A background study of optical chamber experimental data was performed to develop an understanding on the effect of pressure ratio on direct injection of methane under both fully-expanded (sub-sonic) and under-expanded (super-sonic) conditions. Under-expanded jets had a noticeable advantage in terms of turbulent kinetic energy, which led to enhanced air …

Development Of Advanced Models For Pre-Ignition Prediction In Gas Engines And Analytical Model For Wallfilm Evaporation, Ankith Ullal

Dissertations, Master's Theses and Master's Reports

Ever-changing regulations aimed at improving efficiency and reducing harmful emissions have resulted in many power-generation device (engine) manufacturers to adopt new strategies. Computer simulation of these new strategies of power generation requires more accurate and higher fidelity modelling tools. In the present study, two such models are developed. The first model deals with pre-ignition phenomena driven by lubricant (lube) oil in natural gas engines and the second model is relevant to prediction of wallfilm evaporation by employing analytical solutions to transport governing equations for boundary layers.

Pre-ignition in engines has been the subject of current research with the advent of …

Concept Evaluation And Development Of A Novel Approach For Integration Of Turbogeneration, Electrification And Supercharging On Heavy Duty Engines, Satyum Joshi

Dissertations, Master's Theses and Master's Reports

While many technologies such as electrically assisted turbocharging, exhaust energy recovery and mild hybridization have already proven to significantly increase heavy-duty engine efficiency, the key challenge to their widespread adoption has been their cost effectiveness and packaging. This research specifically addresses these challenges through evaluation and development of a novel technology concept termed as the Integrated Turbogeneration, Electrification and Supercharging (ITES) system. The concept integrates a secondary compressor, a turbocompound/expander turbine and an electric motor through a planetary gearset into the engine cranktrain. The approach enables a reduced system cost and space-claim, while maximizing the efficiency benefits of independent technologies. …

Calorimetric Measurements Of Lunar Regolith Simulant And Water. An Experimental Study Correlating Weight Percent Water And Temperature Change Through Periods Of Phase Change., George B. Johnson

Dissertations, Master's Theses and Master's Reports

Permanently Shaded Regions (PSRs) are cold traps located around the lunar south pole that have been confirmed to contain possible interesting quantities or volatiles such as H2O, CO2, SO2, CH4, and others. [1] The identification of these volatiles on the lunar surface was a critical step in the development of NASA’s strategic goals for scientific discoveries, sustained space travel and exploration, and re-establishing a human presence on the moon. These volatiles are vital to the future of operating in and exploring space. The LCROSS impact revealed the existence of these resources in PSRs but more information is needed about the …