Publication Date




Embargo Period


Degree Type


Degree Name

Doctor of Philosophy (PHD)


Mechanical Engineering (Engineering)

Date of Defense


First Committee Member

Michael R. Swain

Second Committee Member

Singiresu S. Rao

Third Committee Member

Paul M. Bevilaqua

Fourth Committee Member

Matthew R. Swain


Many different models exist for internal combustion engines. When designing and optimizing an internal combustion oftentimes key parameters are missing. Commonly no Pressure-Volume diagrams exist. It is the purpose of this dissertation to prove that a simple and accurate model can generate excellent results. The results of the model were verified using three different engine configurations and found to give accurate results for power and BTE. These theoretical results helped to better understand each engine configuration. The three engine configurations varied in swirl and squish. The engine configurations were all tested using propane as a fuel. The three engine configurations were based on the same engine with different cylinder heads. The engine was specifically developed for generator usage in the 15-17kW range. The engine was based on a 1.6L four cylinder engine. The engine was configured for low RPM operation, propane as a fuel, minimal friction and ease of data acquisition. The different cylinder heads had varying squish and swirl in order to better understand their relation to BTE. Of the three configurations tested the Super High Swirl engine configuration had a maximum BTE of 37.5%. This Air-Fuel ratio used was λ=1.66. This engine configuration had 33.9% squish, an average swirl ratio of 3.2 and a compression ratio of 12.7:1. The model was able to capture excellent results between the experimental and theoretical model. The theoretical model was able to capture the additional heat losses from the increased gas velocities associated with squish and swirl, without modifying the heat loss coefficient for each configuration and data set to match experimental results.


Internal Combustion Engine Propane Swirl Squish