Low-Pressure Turbine Cascade Performance Calculations With Incidence Variation and Periodic Unsteady Inflow Conditions

TitleLow-Pressure Turbine Cascade Performance Calculations With Incidence Variation and Periodic Unsteady Inflow Conditions
Publication TypeConference Paper
Year of Publication2015
AuthorsMarconcini M, Pacciani R, Arnone A, Bertini F
Conference NameASME Turbo Expo 2015: Turbine Technical Conference and Exposition
Volume2A: Turbomachinery
Date PublishedJune 15–19
Conference LocationMontreal, Canada
ISBN Number978-0-7918-5663-5
Accession NumberWOS:000380084400049
Other NumbersScopus 2-s2.0-84954312169
KeywordsLow Pressure Turbine; low Reynolds number aerodynamics; Off Design performance; Wake-Induced Transition

The performance of a Low-Pressure Turbine (LPT) cascade were investigated under both steady and periodic unsteady inflow boundary conditions with different Reynolds numbers and a reduced frequency representative of real LPT working conditions. A sensitivity analysis to the variation of the inlet flow angle was performed to assess the performance during off-design operation.
The numerical framework is based on a steady/unsteady Reynolds Averaged Navier-Stokes (RANS/URANS) flow solver which includes some state-of-the-art transition-sensitive turbulence closures. Boundary conditions for the time-accurate computations upstream of the cascade were derived from the experimental characterization of a moving bar system used to generate the wake periodic perturbations.
The computed performance of the cascade, as a function of Reynolds number and incidence angle variation, is discussed in comparison with experimental data. Steady and unsteady boundary layer quantities are also compared with measurements in order to gain more insights into the loss generation process and to better support the numerical results. Such an assessment proves that the proposed procedure is adequate for the analysis of the off-design behavior of cascades operating in low pressure turbine conditions.


ASME paper GT2015–42276

Refereed DesignationRefereed