DNS of Unsteady Turbine Cascade Flow

Flow with upstream passing wakes

velocity magnitude over a xy plane at instant 1

velocity magnitude over a xy plane at instant 2

velocity magnitude over a xy plane at instant 3

velocity magnitude over a xy plane at instant 4

newly discovered longitudinal vortices inside the turbine passage, t1

newly discovered longitudinal vortices inside the turbine passage, t2

newly discovered longitudinal vortices near the concave blade surface, ta

newly discovered longitudinal vortices near the concave blade surface, tb

newly discovered longitudinal vortices near the concave blade surface, tc

newly discovered longitudinal vortices near the concave blade surface, td

newly discovered longitudinal vortices near the concave blade surface, te

fluctuating velocity norm (~tke) over the xy plane

turbulent spot, Lambda vortices on the suction side

spot induced suction-side transition

comparison of DNS and experiments
 

Flow without upstream passing wakes

static pressure over a xy plane at one instant

time-averaged static pressure p

velocity norm over a xy plane at one instant

time-averaged velocity norm

tangential velocity v over a xy plane at one instant

turbulence kinetic energy K over a xy plane at one instant

time-averaged turbulence kinetic energy K
 

Flow with 8% upstream grid turbulence

computation domain and one level of multigrid mesh

a subset of the 87 million computational grid near blade surface

inflow grid turbulence from Dr. Alan Wray -- correlations

inflow grid turbulence from Dr. Alan Wray -- spectrum

coarse-grid velocity norm in one xy plane

coarse-grid fluctuating velocity norm in one xy plane

coarse-grid instantaneous pressure in one xy plane

coarse-grid time-averaged pressure

87 million grid velocity norm in one xy plane on July 24, 2000

87 million grid instantaneous pressure in one xy plane on July 24, 2000
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