This study analyzes the flow over a three-dimensional linear low-pressure turbine cascade blade using large eddy
simulation at Re=90 k. The computational model consists of one blade passage with periodic boundaries and synthetic
turbulence is generated at the inlet of the domain. Various flow metrics, including isentropic Mach number distribution
at mid-span and wake total pressure losses are compared with available experimental data and found to be in good agree-
ment. A more detailed analysis of the turbulence with particular attention to the separation bubble region is subsequently
presented. The analysis revealed that the turbulence is in a nearly two-component state very close to the wall region and
gradually follows a certain anisotropy trajectory, as the distance from the wall increases. Even in the free-stream region
no fully isotropic state is reached, due to large acceleration and flow turning. The results give a new insight into the
state of turbulence within the separation region on the blade suction side and emphasize the deficiencies of the Reynolds-
averaged Navier Stokes (RANS) turbulence models in reproducing the turbulence anisotropy. This insight is of relevance
for the aerodynamic design of turbines, since large parts of the total pressure loss are generated in the separation region.
«This study analyzes the flow over a three-dimensional linear low-pressure turbine cascade blade using large eddy
simulation at Re=90 k. The computational model consists of one blade passage with periodic boundaries and synthetic
turbulence is generated at the inlet of the domain. Various flow metrics, including isentropic Mach number distribution
at mid-span and wake total pressure losses are compared with available experimental data and found to be in good agree-
ment. A more detailed a...
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