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dc.contributor.advisorBogard, David G.en
dc.creatorAlbert, Jason Edwarden
dc.date.accessioned2011-06-09T14:41:01Zen
dc.date.accessioned2011-06-09T14:42:39Zen
dc.date.available2011-06-09T14:41:01Zen
dc.date.available2011-06-09T14:42:39Zen
dc.date.issued2011-05en
dc.date.submittedMay 2011en
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2011-05-3144en
dc.descriptiontexten
dc.description.abstractDeposition of contaminant particles on gas turbine surfaces reduces the aerodynamic and cooling efficiency of the turbine and degrades its materials. Gas turbine designers seek a better understanding of this complicated phenomenon and how to mitigate its effects on engine efficiency and durability. The present study developed an experimental method in wind tunnel facilities to simulate the important physical aspects of the interaction between deposition and turbine cooling, particularly film cooling. This technique consisted of spraying molten wax droplets into the mainstream flow that would deposit and solidify on large scale, cooled, turbine airfoil models in a manner consistent with inertial deposition on turbine surfaces. The wax particles were sized to properly simulate the travel of particles in the flow path, and their adhesion to the surface was modeled by ensuring they remained at least partially molten upon impact. Initial development of this wax spray technique was performed with a turbine blade leading edge model with three rows of showerhead film cooling. It was then applied to turbine vane models with showerhead holes and row on pressure side consisting of either standard cylindrical holes or similar holes situated in a spanwise, recessed trench. Vane models were either approximately adiabatic or had a thermal conductivity selected to simulate the conjugate heat transfer of turbine airfoils at engine conditions. These models were also used to measure the adiabatic film effectiveness and overall cooling effectiveness in order to better assess how the cooling design interacted with deposition. Deposit growth was found to be sensitive to the mainstream air and the model surface temperatures and the solidification temperature of the wax. Deposits typically grew to an equilibrium thickness caused by a balance between erosion and adhesion. The existence of film cooling substantially redistributed deposit growth, but changes in blowing ratio had a minor effect. A hypothesis was proposed and substantiated for the physical mechanisms governing wax deposit growth, and its applicability to engine situations was discussed.en
dc.format.mimetypeapplication/pdfen
dc.language.isoengen
dc.subjectTurbinesen
dc.subjectTurbine coolingen
dc.subjectFilm coolingen
dc.subjectWax sprayen
dc.subjectVane modelen
dc.subjectLeading edge modelen
dc.titleExperimental simulation and mitigation of contaminant deposition on film cooled gas turbine airfoilsen
dc.date.updated2011-06-09T14:42:39Zen
dc.contributor.committeeMemberda Silva, Alexandre K.en
dc.contributor.committeeMemberEzekoye, Ofodike A.en
dc.contributor.committeeMemberWebber, Michael E.en
dc.contributor.committeeMemberWenglarz, Richard A.en
dc.description.departmentMechanical Engineeringen
dc.type.genrethesisen
thesis.degree.departmentMechanical Engineeringen
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.grantorUniversity of Texas at Austinen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen


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