Date of Award


Degree Name

Master of Science in Engineering


Mechanical and Aerospace Engineering

First Advisor

Dr. Bade Shrestha

Access Setting

Masters Thesis-Open Access


Recent energy security and environmental concerns have prompted growing interest into utilization of alternative fuels such as, natural gas and landfill gas. These gaseous fuels contain significant amount of diluents in the fuel composition, such as carbon dioxide, nitrogen, water vapor and other trace gases, which vary by geographical location. Successful engine operation is limited by a phenomenon called "knock", which occurs due to auto-ignition of the end gas ahead of the flame front, and therefore, needs to be investigated with the utilization of these gaseous fuels.

The present contribution discusses the experimental set-up, procedure and results of the investigation of knock in binary mixtures of methane and hydrogen with the presence of varying amounts of diluents, to closely represent the general composition of such gaseous alternative fuels. The knock characteristics were investigated using two methods namely, knock limited spark timing and knock limited compression ratio. From the empirical analysis, it was determined that, the addition of diluents, such as carbon dioxide and nitrogen to the binary mixtures, augmented the knock resistance characteristics to extend the engine operating limits.