Search VTechWorks



Advanced Search

Browse

My Account

Statistics

Watch Registration Video

Return to Skip Menu .

Main Content

Show simple item record

dc.contributor.author Blot, Dorian Matthew en_US
dc.date.accessioned 2013-02-19T22:41:10Z
dc.date.available 2013-02-19T22:41:10Z
dc.date.issued 2013-01-23 en_US
dc.identifier.other vt_gsexam:159 en_US
dc.identifier.uri http://hdl.handle.net/10919/19257
dc.description.abstract      Endwall contouring has been widely studied as an effective measure to improve aerodynamic performance by reducing secondary flow strength. The effects of endwall contouring with discrete holes and an upstream purge slot for a high turning (127") airfoil passage under transonic conditions are investigated. The total pressure loss and secondary flow field were measured for two endwall geometries. The non-axisymmetric endwall was developed through an optimization study [1] to minimize secondary losses and is compared to a baseline planar endwall. The blade inlet span increased by 13 degrees with respect to the inlet in order to match engine representative inlet/exit Mach number loading in a HP turbine.  The experiments were performed in a quasi-2D linear cascade with measurements at design exit Mach number 0.88 and incidence angle. Four cases were analyzed for each endwall -- the effect of slot presence (with/without coolant) and the effect of discrete holes (with/without coolant) without slot injection. The coolant to mainstream mass flow ratio was set at 1.0% and 0.25% for upstream purge slot and discrete holes, respectively.  Aerodynamic loss coefficient is calculated with the measured exit total pressure at 0.1 Cax downstream of the blade trailing edge. CFD studies were conducted in compliment. The aero-optimized endwall yielded lower losses than baseline without the presence of the slot. However, in presence of the slot, losses increased due to formation of additional vortices. For both endwall geometries, results reveal that the slot has increased losses, while the addition of coolant further influences secondary flow development. en_US
dc.format.medium ETD en_US
dc.publisher Virginia Tech en_US
dc.rights The authors of the theses and dissertations are the copyright owners. Virginia Tech's Digital Library and Archives has their permission to store and provide access to these works. en_US
dc.subject Gas Turbines en_US
dc.subject Transonic Cascade en_US
dc.subject Aerodynamics. Heat Transfer en_US
dc.subject Film Cooling en_US
dc.subject Upstream Purge Slot en_US
dc.subject Discrete Hole Cooling en_US
dc.subject Endwall en_US
dc.title Aerodynamics of Endwall Contouring with Discrete Holes and an Upstream Purge Slot Under Transonic Conditions  with and without Blowing en_US
dc.type Thesis en_US
dc.contributor.department Mechanical Engineering en_US
dc.description.degree MS en_US
thesis.degree.name MS en_US
thesis.degree.level masters en_US
thesis.degree.grantor Virginia Polytechnic Institute and State University en_US
thesis.degree.discipline Mechanical Engineering en_US
dc.contributor.committeechair Ekkad, Srinath en_US
dc.contributor.committeechair Ng, Wing Fai en_US
dc.contributor.committeemember O'Brien, Walter F en_US

Files in this item


This item appears in the following Collection(s)

Show simple item record

.