Experimental investigation of boundary layer separation control using steady vortex generator jets on low pressure turbines

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2012
Doğan, Eda
This thesis presents the results of an experimental study that investigates the effects of steady vortex generator jets (VGJs) integrated to a low pressure turbine blade to control the laminar separation bubble occurring on the suction surface of the blade at low Reynolds numbers. The injection technique involves jets issued from the holes located near the suction peak of the test blade which is in the middle of a five-blade low speed linear cascade facility. Three injection cases are tested with different blowing ratio values ranging from low to high. Surface pressure and particle image velocimetry (PIV) measurements are performed. The results show that steady VGJ is effective in eliminating the laminar separation bubble. Also it is observed that to have fully developed attached boundary layer, blowing ratio should be chosen accordingly since a very thin separation zone still exists at low blowing ratios.

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Citation Formats
E. Doğan, “Experimental investigation of boundary layer separation control using steady vortex generator jets on low pressure turbines,” M.S. - Master of Science, Middle East Technical University, 2012.