naa a22 4500 510766234 CHVBK 20180411083157.0 cr unu---uuuuu 180411e20131001xx s 000 0 eng 10.1007/s11630-013-0643-9 doi (NATIONALLICENCE)springer-10.1007/s11630-013-0643-9 A comparison of experimental and numerical studies performed on a low-pressure turbine blade cascade at high-speed conditions, low reynolds numbers and various turbulence intensities [Elektronische Daten] [Jan Michalek, Petr Straka] This paper focuses on a comparison of experimental and numerical investigations performed on a low-pressure mid-loaded turbine blade at operating conditions comprised of a wide range of Mach numbers (from 0.5-1.1), Reynolds numbers (from 0.4e+5-3.0e+5), flow incidence (−15-15 degrees) and three levels of free-stream turbulence intensities (2, 5 and 10%). The experimental part of the work was performed in a high-speed linear cascade wind tunnel. The increased levels of turbulence were achieved by a passive grid placed at the cascade inlet. A two-dimensional flow field at the center of the blade was traversed pitch-wise upstream and downstream the cascade by means of a five-hole probe and a needle pressure probe, respectively. The blade loading was measured using the surface pressure taps evenly deployed at the blade mid-span along the suction and the pressure side. The inlet turbulence was investigated using the constant temperature anemometer technique with a dual sensor probe. Experimentally evaluated values of turbulent kinetic energy and its dissipation rate were then used as inputs for the numerical simulations. An in-house code based on a system of the Favre-averaged Navier-Stokes equation closed by a two-equation k-ω turbulence model was adopted for the predictions. The code utilizes an algebraic model of bypass transition valid both for attached as for separated flows taking in account the effect of free-stream turbulence and pressure gradient. The resulting comparison was carried out in terms of the kinetic energy loss coefficient, distributions of downstream wakes and blade velocity. Additionally a flow visualization was performed by means of the Schlieren technique in order to provide a further understanding of the studied phenomena. A few selected cases with a particular interest in the attached and separated flow transition are compared and discussed. Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag Berlin Heidelberg, 2013 low pressure turbine nationallicence high-speed flow nationallicence low Reynolds number nationallicence flow separation nationallicence transition nationallicence RANS nationallicence Michalek Jan VZLU — Aerospace Research and Test Establishment Beranových 130, 195 00, Prague, Czech Republic aut Straka Petr VZLU — Aerospace Research and Test Establishment Beranových 130, 195 00, Prague, Czech Republic aut Journal of Thermal Science Springer Berlin Heidelberg 22/5(2013-10-01), 413-423 1003-2169 22:5<413 2013 22 11630 https://doi.org/10.1007/s11630-013-0643-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11630-013-0643-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Michalek Jan VZLU — Aerospace Research and Test Establishment Beranových 130, 195 00, Prague, Czech Republic aut NATIONALLICENCE 700 1- Straka Petr VZLU — Aerospace Research and Test Establishment Beranových 130, 195 00, Prague, Czech Republic aut NATIONALLICENCE 773 0- Journal of Thermal Science Springer Berlin Heidelberg 22/5(2013-10-01), 413-423 1003-2169 22:5<413 2013 22 11630 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer