TY - GEN
T1 - The influence of wake passing frequency and elevated free stream turbulence intensity on transition in low-pressure turbines
AU - Kaszeta, Richard W.
AU - Simon, Terrence W
AU - Ottaviani, Federico
AU - Jiang, Nan
PY - 2003
Y1 - 2003
N2 - Experimental results from a study of the effects of passing wakes upon laminar-to-turbulent transition in a low-pressure turbine passage are presented. The test section geometry is designed to simulate the effects of unsteady wakes resulting from rotor-stator interaction in turbine blade boundary layers and separated flow regions over suction surfaces. Single-wire, thermal anemometry techniques are used to measure timeresolved and phase-averaged, wall-normal profiles of velocity, turbulence intensity and intermittency at multiple streamwise locations over the turbine airfoil suction surface. The Reynolds number based on suction surface length and stage exit velocity is 50,000. This study compares cases of either decreased wake passing frequency or elevated approach flow turbulence intensity to data from a base case. The results show that the decreased wake frequency from that of the base case results in an earlier separation with a larger separation bubble, while data from the elevated FSTI case show an further downstream separation, but a shorter, thinner, separation bubble than observed in the base case.
AB - Experimental results from a study of the effects of passing wakes upon laminar-to-turbulent transition in a low-pressure turbine passage are presented. The test section geometry is designed to simulate the effects of unsteady wakes resulting from rotor-stator interaction in turbine blade boundary layers and separated flow regions over suction surfaces. Single-wire, thermal anemometry techniques are used to measure timeresolved and phase-averaged, wall-normal profiles of velocity, turbulence intensity and intermittency at multiple streamwise locations over the turbine airfoil suction surface. The Reynolds number based on suction surface length and stage exit velocity is 50,000. This study compares cases of either decreased wake passing frequency or elevated approach flow turbulence intensity to data from a base case. The results show that the decreased wake frequency from that of the base case results in an earlier separation with a larger separation bubble, while data from the elevated FSTI case show an further downstream separation, but a shorter, thinner, separation bubble than observed in the base case.
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M3 - Conference contribution
AN - SCOPUS:84896692684
SN - 9781624100970
T3 - 36th AIAA Thermophysics Conference
BT - 36th AIAA Thermophysics Conference
T2 - 36th AIAA Thermophysics Conference 2003
Y2 - 23 June 2003 through 26 June 2003
ER -