Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Characterization of intermittent extreme events in adiabatic and isothermal supersonic turbine cascades
Submission Author:
Gabriel Yudi Ragni Hamada , SP
Co-Authors:
Gabriel Yudi Ragni Hamada, Hugo Felippe da Silva Lui, William Wolf, Tulio Rodarte Ricciardi, Carlos JUNQUEIRA-JUNIOR
Presenter: Gabriel Yudi Ragni Hamada
doi://10.26678/ABCM.COBEM2023.COB2023-0538
Abstract
We investigate extreme events occurring in the shock-boundary layer interactions (SBLIs) of a supersonic turbine cascade. The present analysis is performed considering adiabatic and isothermal blades, where for the latter the wall to inlet temperature ratio is $T_w/T_\infty = 0.75$, representing a cooled wall. The supersonic flows are computed by wall-resolved large eddy simulations (LES) for an inlet Mach number $M_\infty = 2.0$ and Reynolds number based on the axial chord $Re = 2\times10^5$. Different incident shock wave topologies are observed on the suction and pressure sides of the airfoil. For the former, an oblique shock impinges on the boundary layer leading to a more pronounced separation bubble. On the other hand, for the latter, a normal shock forms in a Mach reflection, inducing a small separation bubble near the wall. Results are presented in terms of the conditional proper orthogonal decomposition (CPOD) modes for the tangential and normal velocity components, as well as pressure. These modes are presented for three different time instants to characterize the cause and effect of the extreme events in the flowfield.
Keywords
shock boundary layer interaction, supersonic turbine, LES, CPOD
