Engineering Commons^™

Design And Implementation Of An Oxidation Catalyst For A Spark Ignited Two Stroke Snowmobile Engine, Noah Squires

Dissertations, Master's Theses and Master's Reports

Spark ignited two stroke engines are under increasing pressure as emissions standards become stricter, making them a perfect candidate for a catalytic aftertreatment system. Yet several significant challenges to catalysis exist. Namely two stroke exhaust systems are very sensitive to back pressure changes and high emissions concentrations can make controlling the temperature of the catalytic reaction difficult. Therefore, it is imperative that a two stroke specific catalyst design process be developed. This project focused on beginning to develop such a design process. Key results of this work include finding a location for the catalyst in the exhaust system that offers …

Effects Of Variable Valve Actuation On Exhaust Enthalpy And Engine Out Emissions, Zakarie Parker

Dissertations, Master's Theses and Master's Reports

Vehicle emissions standards are becoming increasingly more strict as time progresses. Once all of the emissions devices are in their operational stage, these standards can be met with reasonable effort in powertrain design and calibration. However, the core of this system, the three-way catalyst, is non-operational until it has reached 200-350⁰C. Because of this, cold-start catalyst heating is extremely important in new vehicles. The objective of this project was to improve catalyst heating without increasing engine-out emissions. It was decided that the sensible heat portion of the exhaust enthalpy would be the best metric to judge differences between the different …

Development Of A 2d Scr Catalyst On A Diesel Particulate Filter Model For Design And Control Applications To A Ultra Low Nox Aftertreatment System, Venkata Chundru

Dissertations, Master's Theses and Master's Reports

This research focuses on modeling and control of PM and NO_x in diesel engine exhaust using an SCR catalyst on a Diesel Particulate Filter (SCR-F). A 2D SCR-F model was developed that is capable of predicting internal states: 2D temperature, PM and NH₃storage distributions and filtration efficiency, pressure drop, PM mass retained in the PM cake and substrate wall and outlet NO, NO₂and NH₃concentrations. The SCR-F model was used to simulate a DOC + SCR-F + DOC + SCR ultra-low NOx system that can achieve > 99.5% NOx conversion efficiency.

The model was calibrated …

Life Cycle Assessment (Lca) Of Ore Transportation Route Alternatives For Eagle Mine, Soumith Kumar Oduru

Dissertations, Master's Theses and Master's Reports

Transportation sector at large is a major consumer of fossil fuels and constitutes more than a quarter of the global greenhouse gas emissions. When making infrastructure route and mode choice decisions for new freight-oriented projects, it is important that environmental and emissions considerations are included as an integral part of the selection process. Emissions from freight transportation projects related to mining and natural resource industry are especially critical, as they involve high volumes and tonnages often in pristine environments. The most logical time for emissions analysis is during modal and route analysis that are often conducted in the planning stage …

Incorporation Of Higher Carbon Number Alcohols In Gasoline Blends For Application In Spark-Ignition Engines, Kristina Lawyer

Dissertations, Master's Theses and Master's Reports

The 2007 U.S. Renewable Fuel Standard (RFS2) requires an increase in the use of advanced biofuels up to 36 billion gallons by 2022. Higher carbon number alcohols, in addition to cellulosic ethanol and synthetic biofuels, could be used to meet this demand while adhering to the RFS2 corn-based ethanol limitation. Alcohols of carbon numbers 2 through 8 are chosen based on their chemical and engine-related properties.

Blend comparison metrics are developed from automotive industry trends, consumer expectations, U.S. fuel legislation, and engine requirements. The metrics are then used to create scenarios by which to compare higher alcohol fuel blends to …

An Experimental Investigation Into The Effect Of Particulate Matter On Nox Reduction In A Scr Catalyst On A Dpf, Saksham Gupta

Dissertations, Master's Theses and Master's Reports

The study of NO_x reduction across the SCRF^® is presented in this report to understand the inlet and outlet NO, NO₂, NH₃ species from the SCRF^®. The SCRF^® is a prototype SCR catalyst on a Diesel Particulate Filter (DPF) that reduces NOx and PM at the downstream location. The SCRF^® reduces the packaging volume of the aftertreatment components in order to reduce the cost, volume and weight of the aftertreatment system. A total of 12 experiments were performed on a Cummins ISB 2013 280 hp engine and the aftertreatment system. The …