Shear Layer Investigation through a High-Load Cascade in Low-Pressure Gas Turbine Conditions
This paper deals with the steady and unsteady flow behavior on the separation bubble occurring on the rear portion of the suction side of T106A blade. The first phase was to implement the steady condition capturing the separation bubble. To accurately predict the separated region, the effects of three different turbulence models and computational grids were separately investigated. The results of Large Eddy Simulation (LES) model on the finest grid structure are acceptably in a good agreement with its relevant experimental results. The second phase is mainly to address the effects of wake entrance on bubble disappearance in unsteady situation. In the current simulations, from what was suggested in an experiment, simulating the flow unsteadiness, with concentrations on small scale disturbances instead of simulating a complete oncoming wake, is the key issue. Subsequently, the results from the current strategy to apply the effects of the wake and two other experimental work were compared to be in a good agreement. Between the two experiments, one of them deals with wake passing unsteady flow, and the other one implements experimentally the same approach as the current Computational Fluid Dynamics (CFD) simulation.
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 Hodson, H.P. and Howell, R.J., “Bladerow Interactions, Transition, and High-Lift Aerofoils in Low-Pressure Turbines,” Annual Review of Fluid Mechanics, vol. 37, pp. 71-98, 2005.
 Stieger, R. and Hodson, H.P., “The Transition Mechanism of Highly Loaded LP Turbine Blades,” Journal of Turbomachinery-Transactions of ASME, vol. 126, No. 4, pp. 536-543, 2004.
 Stieger, R. and Hodson, H.P., “The Unsteady development of a Turbulent Wake Through a Downstream Low-Pressure Turbine Blade Passage,” Journal of Turbomachinery-Transactions of ASME, vol. 127, pp. 388-394, 2005.
 Lodefier, K. and Dick, E., “Modeling of Unsteady Transition in Low Pressure Turbine Blade Flows with Two Dynamic Intermittency Equations,” Flow, Turbulence and Combustion, vol. 76, pp. 103–132, 2005.
 Wissink, J.G., Rodi, W., and Hodson, H.P., “The Influence of Disturbances Carried by Periodically Incoming Wakes on the Separating Flow Around a Turbine Blade,” Int. J. Heat and Fluid Flow, vol. 27, pp. 721-729, 2006.
 Opoka M.M., Thomas, R.L., and Hodson H.P., “Boundary Layer Transition on the High Lift T106A Low-Pressure Turbine Blade with an Oscillating Downstream Pressure Field,” Journal of Turbomachinery-Transactions of ASME, vol. 130, No. 2, Article number 021009, 2008.
 Calzada, P.D.L., and Alonso, A., “Numerical Investigation of Heat Transfer in Turbine Cascades with Separated Flows,” Journal of Turbomachinery-Transactions of ASME, vol. 125, no. 2, pp. 260–266, 2003.
 H. P. Hodson and R. G. Dominy, ASME J. Turbomach. 109, 201 (1987).
 X. Wu and P. A. Durbin, “Evidence of longitudinal vortices evolved from distorted wakes in a turbine passage,” J. Fluid Mechanics, vol. 446, P. 199–228, 2001.
 V. Michelassi, J. G. Wissink, J. Fröhlich, and W. Rodi, “Large-eddy simulation of flow around low-pressure turbine blade with incoming wakes,” AIAA J., vol. 41, no. 11, P. 2143–2156, 2003.
 K. Matsuura and C. Kat, “Large-eddy simulation of compressible transitional flows in a low-pressure turbine cascade,” AIAA J., vol. 45, no. 2, P. 442–457, 2007.
 C. Velez, P. Coronado, H. Al-Kuran, and M. Ilie, “Numerical computations of turbine blade aerodynamics; comparison of LES, SAS, SST, SA, and k-ε,” AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2011.
 A. Ghidoni, A. Colombo, S. Rebay, and F. Bassi, “Simulation of the transitional flow in a low pressure gas turbine cascade with a high-order discontinuous galerkin method,” ASME Journal of Fluids Engineering, Vol. 135, No. 7, P. 071101-1–071101-8, 2013.
 R., E. Mayle, “The Role of Laminar-Turbulent Transition in Gas Turbine Engines,” J. Turbomachinery, vol. 113, no. 4, pp. 509-536, 1991.
 M. Stieger, W. Richtering, J. S. Pedersen, and P. Lindner, “Small-angle neutron scattering study of structural changes in temperature sensitive microgel colloids,” The Journal of chemical physics, vol. 120, no. 13, pp.6197-6206, 2004.
 OpenFOAM project web pages http://www.openfoam.com, accessd 01/04/2014.
 Cobley, K., Coleman, N., Siden, G., Arndt, N., 1997, “Design of new three stage low pressure turbine for BMW Rolls-Royce BR715 engine”, ASME 97-GT-419.
 Hoheisel, H., “Test Case E/CA-6, Subsonic Turbine Cascade T106, Test Cases for Computation of Internal Flows in Aero Engine Components,” AGARD-AR-275, 1990.
 T. Hildebrandt and L. Fottner, “A numerical study of the influence of grid refinement and turbulence modeling on the flow field inside a highly loaded turbine cascade,” J. Turbomachinery, vol. 121, no. 4, pp. 709–716, 1999.
 David C Wilcox, Turbulence Modeling for CFD, 3rd ed. DCW Industries, Inc., 2006, 522 pages.
 Roach, P. E., 1987, “The Generation of Nearly Isotropic Turbulence by Means of Grids,” Int. J. Heat Fluid Flow, 8(2), pp. 82–92.