Download or read book Experimental Study of Transitional Flow Behavior in a Simulated Low Pressure Turbine written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-24 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed investigation of the flow physics occurring on the suction side of a simulated Low Pressure Turbine (LPT) blade was performed. A contoured upper wall was designed to simulate the pressure distribution of an actual LPT airfoil onto a flat lower plate. The experiments were carried out for the Reynolds numbers of 35,000, 70,000, 100,000 and 250,000 with four levels of freestream turbulence ranging from 1% to 4%. For the three lower Reynolds numbers, the boundary layer on the flat plate was separated and formed a bubble. The size of laminar separation bubble was measured to be inversely proportional to the freestream turbulence levels and Reynolds numbers. However, no separation was observed for the Re = 250,000 case. The transition on a separated flow was found to proceed through the formation of turbulent spots in the free shear layer as evidenced in the intermittency profiles for Re = 35,000, 70,000 and 100,000. Spectral data show no evidence of Kelvin-Helmholtz or Tollmien-Schlichting instability waves in the free shear layer over a separation bubble (bypass transition). However, the flow visualization revealed the large vortex structures just outside of the bubble and their development to turbulent flow for Re = 50,000, which is similar to that in the free shear layer (separated-flow transition). Therefore, it is fair to say that the bypass and separated-flow transition modes coexist in the transitional flows over the separation bubble for certain conditions. Transition onset and end locations and length determined from intermittency profiles decrease as Reynolds number and freestream turbulence levels increase. Sohn, Ki Hyeon and DeWitt, Kenneth J. Glenn Research Center NCC3-288...

Download or read book Experimental Study of Transitional Flow Behavior in a Simulated Low Pressure Turbine written by Nasa Technical Reports Server (Ntrs) and published by BiblioGov. This book was released on 2013-07 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NASA Technical Reports Server (NTRS) houses half a million publications that are a valuable means of information to researchers, teachers, students, and the general public. These documents are all aerospace related with much scientific and technical information created or funded by NASA. Some types of documents include conference papers, research reports, meeting papers, journal articles and more. This is one of those documents.

Download or read book Experimental Investigation of Boundary Layer Behavior in a Simulated Low Pressure Turbine written by Ki-Hyeon Sohn and published by . This book was released on 1998 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of Boundary Layer Behavior in a Simulated Low Pressure Turbine written by Rickey J. Shyne and published by . This book was released on 1998 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book EXPERIMENTAL STUDY OF BOUNDARY LAYER BEHAVIOR IN A SIMULATED LOW PRESSURE TURBINE NASA TM 1998 208503 JAN 20 1999 written by United States. National Aeronautics and Space Administration and published by . This book was released on 1999* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book EXPERIMENTAL INVESTIGATION OF BOUNDARY LAYER BEHAVIOR IN A SIMULATED LOW PRESSURE TURBINE NASA TM 1998 207921 SEP 15 1998 written by United States. National Aeronautics and Space Administration and published by . This book was released on 1999* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbulent Transition Behavior in a Separated and Attached flow Low Pressure Turbine Passage written by Curtis L. Memory and published by . This book was released on 2010 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Various time accurate numerical simulations were conducted on the aft-loaded L1A low pressure turbine airfoil operating at Reynolds numbers presenting with fully-stalled, non-reattaching laminar separation. The numerical solver TURBO was modified from its annular gas turbine simulation configuration to conduct simulations based on a linear cascade wind tunnel facility. Simulation results for the fully separated flow fields revealed various turbulent decay mechanisms. Separated shear layer decay, in the form of vortices forming between the shear layer and the blade wall, was shown to agree with experimental particle image velocimetry (PIV) data in terms of decay vortex size and core vorticity levels. These vortical structures eventually mix into a large recirculation zone which dominates the blade wake. Turbulent wake extent and time-averaged velocity distributions agreed with PIV data. Steady-blowing vortex generating jet (VGJ) flow control was then applied to the flow fields. VGJ-induced streamwise vorticity was only present at blowing ratios above 1.5. VGJs actuated at the point of flow separation on the blade wall were more effective than those actuated downstream, within the separation zone. Pulsed-blowing VGJs at the upstream blade wall position were then actuated at various pulsing frequencies, duty cycles, and blowing ratios. These condition variations yielded differing levels of separation zone mitigation. Pulsed VGJs were shown to be more effective than steady blowing VGJs at conditions of high blowing ratio, high frequency, or high duty cycle, where blowing ratio had the highest level of influence on pulsed jet efficacy. The characteristic "calm zone" following the end of a given VGJ pulse was observed in simulations exhibiting high levels of separation zone mitigation. Numerical velocity fields near the blade wall during this calm zone was shown to be similar to velocity fields observed in PIV data. Instantaneous numerical vorticity fields indicated that the elimination of the separation zone directly downstream of the VGJ hole is a primary indicator of pulsed VGJ efficacy. This indicator was confirmed by numerical time-averaged velocity magnitude rms data in the same region.

Download or read book Proceedings of the ASME Turbo Expo 2002 Presented at the 2002 ASME Turbo Expo June 3 6 2002 Amsterdam the Netherlands written by and published by . This book was released on 2002 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation This is Volume 1 of five volumes that comprise the proceedings of the June 2002 conference, sponsored by the International Gas Turbine Institute (IGTI), a technical institute of the American Society of Mechanical Engineers. The purpose of the conference was to facilitate international exchange and development of educational and technical information related to the design, application, manufacture, operation, maintenance, and environmental impact of all types of gas engines. With an emphasis upon the need for more efficient, cleaner, and more reliable gas turbines, the approximately 130 articles cover various technical aspects of aircraft engines; coal, biomass, and alternative fuels; combustion and fuels; education; electric power; and vehicular and small turbomachines. There is no subject index. Annotation c. Book News, Inc., Portland, OR (booknews.com).

Download or read book Proceedings of the ASME Turbo Expo written by and published by . This book was released on 2005 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Low Reynolds Number written by Mustafa Serdar Genç and published by BoD – Books on Demand. This book was released on 2012-04-04 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reports the latest development and trends in the low Re number aerodynamics, transition from laminar to turbulence, unsteady low Reynolds number flows, experimental studies, numerical transition modelling, control of low Re number flows, and MAV wing aerodynamics. The contributors to each chapter are fluid mechanics and aerodynamics scientists and engineers with strong expertise in their respective fields. As a whole, the studies presented here reveal important new directions toward the realization of applications of MAV and wind turbine blades.

Download or read book Paper written by and published by . This book was released on 2001 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of Fluids Engineering written by and published by . This book was released on 2008 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ASME Technical Papers written by and published by . This book was released on 2001 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Studies of Low pressure Turbine Flows and Flow Control written by Ralph John Volino and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Investigation of Transition as Applied to Low Pressure Turbine Suction Surface Flows written by Songgang Qiu and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine & Aeroegine Congress & Exhibition, Orlando, FL, Jun 2-Jun 5, 1997.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 974 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of Boundary Layer Development in a Two Stage Low Pressure Turbine written by Daniel J. Dorney and published by . This book was released on 1999 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: