Date of Award

January 2015

Degree Type


Degree Name

Doctor of Philosophy (PhD)


Mechanical Engineering

First Advisor

Nicole L Key

Committee Member 1

Hyoun-Woo Shin

Committee Member 2

Guillermo Paniagua

Committee Member 3

Aaron J King

Committee Member 4

Patricia Davies


The effect of rotor tip clearances in turbomachinery applications has been a primary research interest for nearly 80 years. Over that time, studies have shown increased tip clearance in axial flow compressors typically has a detrimental effect on overall pressure rise capability, isentropic efficiency, and stall margin. With modern engine designs trending toward decreased core sizes to increase propulsive efficiency (by increasing bypass ratio) or additional compression stages to increase thermal efficiency by increasing the overall pressure ratio, blade heights in the rear stages of the high pressure compressor are expected to decrease. These rear stages typically feature smaller blade aspect ratios, for which endwall flows are more important, and the rotor tip clearance height represents a larger fraction of blade span. As a result, data sets collected with large relative rotor tip clearance heights are necessary to facilitate these future small core design goals.