LARGE EDDY SIMULATION OF TANDEM BLADE STATOR CASCADES

Mitra, Pratik and Kantharaju, Jahnavi and Rayan, Rohan and Mathew, Joseph (2017) LARGE EDDY SIMULATION OF TANDEM BLADE STATOR CASCADES. In: ASME Turbo Expo: Turbine Technical Conference and Exposition, JUN 26-30, 2017, Charlotte, NC.

PDF PRO_ASM_EXP_VOL2A_2017.pdf - Published Version Restricted to Registered users only Download (860kB) | Request a copy

Abstract

Large eddy simulations of tandem blade compressor cascades have been performed with an explicit filtering method. A low speed case was simulated using the public domain code Incompact3d which solves incompressible flow with an immersed boundary method for embedded solid bodies, obviating the effort expended on preparing good quality meshes around blading. The LES successfully captures transition on the front blade and yields a significantly different loading compared with RANS solutions obtained before. The less substantial impact on the rear blade is traced to rapid transition forced by the turbulent wake of the front blade. LES with a refined grid was found to shorten the transition width due to the crucial role of small scales during transition. A complementary study with an in-house compressible LES solver was conducted for a transonic tandem cascade at the inlet Mach number of 0.89. Flow expands around the leading edge of the front blade and is terminated by a shock which interacts with the suction surface boundary layer. The beneficial effect of tandem blading was found to be achieved by limiting this separation. The shock-induced separation also marks a rapid transition of the suction surface boundary layer that is readily captured in the LES, showing pre-transitional streaks, but could prove difficult even for current transition-sensitive RANS.

Item Type:	Conference Proceedings
Additional Information:	Copy right for this article belongs to the AMER SOC MECHANICAL ENGINEERS, THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA
Department/Centre:	Division of Mechanical Sciences > Aerospace Engineering(Formerly Aeronautical Engineering)
Date Deposited:	03 Nov 2017 10:44
Last Modified:	03 Nov 2017 10:44
URI:	http://eprints.iisc.ac.in/id/eprint/58174

Actions (login required)

View Item