Date of Award


Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Mechanical Engineering (MS)

Administrative Home Department

Department of Mechanical Engineering-Engineering Mechanics

Advisor 1

Scott Miers

Committee Member 1

Jason Blough

Committee Member 2

Jeremy Worm

Committee Member 3

Brian Eggart

Committee Member 4

David Wanless


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 significant catalyst sizing freedom as well as exploring methods to estimate catalyst back pressure contributions and approximate conversion efficiency targets. Finally, using this design process, 3 actively coated catalyst samples were tested and showed significant reductions in HC and CO with less than a 2 Hp peak power loss.