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Quantification Of Velocity At The Sparkplug In A Lab Scale Combustion Chamber, Mayur Panduranga Kodikal

Electronic Theses and Dissertations

Lean burn has been considered an effective strategy to improve the thermal efficiency of spark-ignition engines. Under lean or diluted conditions, however, the combustion speed is reduced. Therefore, to speed up the combustion, in-cylinder turbulence is induced which may impede the spark initiation. This research aims to quantify the turbulence in a constant volume optical combustion chamber.

An Improved Delayed Detached Eddy Simulation (IDDES) study was done to understand the turbulence characteristics of the flow in the optical chamber. Spark anemometry was used to obtain a relationship between the spark plasma evolution and freestream velocity. Finally, this technique has been …

Cfd Study Of Aerodynamic Drag Reduction Tool Of A Generic Sports Utility Vehicle (Suv), Samira Ishrat Jahan

Masters Theses

The Sports Utility Vehicle (SUV) has been a popular automobile choice in North America for over 50 years due to its seating and hauling versatility and good towing capacity. This widespread popularity has resulted in manufacturers pushing for increased horsepower and cabin size. Unfortunately, the limiting factor has been fuel economy which is governed by the vehicle aerodynamics. A reduction in aerodynamic drag can result in better fuel economy. The goal of this study is to reduce the aerodynamic drag of a generic SUV and the efficient application of drag reduction devices to control flow separation. An initial study has …

Study Of Cooling-Drag In A Generic Passenger Car Using Cfd And Wind Tunnel, Md Maruf Hossain

Masters Theses

The focus of the study is to explore aerodynamic aspects of cooling airflow. As a result of this study, an efficient multi-domain aero-thermal model was developed to analyze the cooling drag of a generic passenger vehicle. Cooling drag is described as the additional force that the production vehicle has to overcome while moving in comparison to the force if all the openings were closed. Though this model was developed based on the sedan class vehicle, the applied methodology could be generalized for other ground vehicle types. As a part of the presented model, a unique simplified geometric model is developed …

Modeling And Analysis Of Reactivity Controlled Compression Ignition (Rcci) Combustion, Mohammadreza Nazemi

Dissertations, Master's Theses and Master's Reports - Open

Homogeneous Charge Compression Ignition (HCCI) and Premixed Charge Compression Ignition (PCCI) combustion strategies are promising methods for achieving low engine-out NOx and soot emissions as well as high indicated efficiency. However, these combustion strategies have difficulties with controlling the rate of heat release and lack of an adequate combustion phasing control mechanism. A dual-fuel Reactivity Controlled Compression Ignition (RCCI) combustion strategy will address these issues due to the existence of precise means for controlling the heat release rate and combustion phasing. In the RCCI strategy two fuels with different reactivity (auto-ignition characteristics, e.g., gasoline and diesel) are blended inside the …