Comparison of RANS and U-RANS for Flat Plate Film Cooling

Abstract:

Film cooling has been extensively used to provide thermal protection for the external surfaces of gas turbine components. For the past 40 years, numerous number of film cooling hole designs and arrangements have been introduced. Due to broad designs and arrangements of film cooling, numerical investigation has been utilized to provide initial insight on the aerodynamics and thermal performance of the new film cooling designs or arrangements. The present work focuses on the numerical investigation of RANS and URANS analyses on a flat plate film cooling. The investigation aims to provide comparison between various turbulent models available for the Reynolds Average Navier Stokes (RANS) analyses and extended to unsteady Reynolds Average Navier Stokes (URANS). The numerical investigations make used of ANSYS CFX ver. 14 and were carried out at Reynolds Number, Re = 7,000 based on the hole diameter at blowing ratio, BR = 0.5. The results of the RANS analyses show significant influence of the turbulent models on the predicted aerodynamics and thermal performance of the film cooling. The result of URANS indicates limitation of RANS analyses to provide details on the eddied and vortices formation in film cooling flow structure.

• Periodical: Applied Mechanics and Materials (Volumes 773-774)
• Pages: 353-357
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.773-774.353
• Online since: July 2015
• Authors: Kamil Abdullah*, Osama H. Abdulguad, Akmal Nizam Mohammed, Zaid Suleiman
• Keywords: CFD, CFX, Flat-Plate Film-Cooling, RANS, URANS

References

[1] Meherwan P.B., 2002, Gas Turbine Engineering Handbook, 2nd edition, Gulf Professional Publishing, Houston, Texas, 800, pp.3-23.

[2] Han, J.C., Dutta, S., and Ekkad, S, 2000, Gas Turbine Heat Transfer and Cooling Technology, Taylor and Francis, New York, pp.129-436.

[3] Andreopoulos, J., Rodi, W., 1984 Experimental Investigation of Jets in a Crossflow, J. of Fluid Mechanics, Vol. 138, pp.93-127.

DOI: 10.1017/s0022112084000057

[4] Fric, T.F., Roshko, A., 1994, "Vortical Structure in the Wake of Transverse Jet. J. of Fluid Mechanics, Vol, 279, pp.1-47.

DOI: 10.1017/s0022112094003800

[5] Pietrzyk, J.R., Crawford, M.E., Bogard, D.G., 1988, Hydrodynamic Measurements of Jets in Crossflow for Gas Turbine Film Cooling Applications, ASME Paper No. 88/GT/174.

DOI: 10.1115/1.3262248

[6] Pietrzyk, J.R., 1989, Experimental Study of the Interaction of Dense Jets with a Crossflow for Gas Turbine Applications, PhD Thesis, University of Texas at Austin.

[7] Goldstein R.J., Eckert, E.R.G., and Burggraf, F, 1974, Effect of Hole Geometry and Density on Three Dimensional Film Cooling, Int. J. Heat Mass Transfers, Vol. 17, pp.595-607.

DOI: 10.1016/0017-9310(74)90007-6

[8] Ely M.J., and Jubran, B.A., 2009, A Numerical Evaluation On The Effect Of Sister Holes On Film Cooling Effectiveness And The Surrounding Flow Field,J. Heat Mass Transfers, Vol. 45, pp.1435-1446.

DOI: 10.1007/s00231-009-0523-8

[9] Ekkad, S.V., Heidmann, J., Dhungel, A., Lu, Y., and Wynn P., 2009, Film Cooling From a Row of Holes Supplemented with Antivortex Holes, ASME J. Turbomachinery, Vol. 131, pp.021007-10.

DOI: 10.1115/1.2950059

[10] Kamil, A., Funazaki, K., Onodera, H., and Ideta, T., 2012, Experimental Investigations on Aero-Thermal Interaction of Film Cooling Air Ejected from Multiple Holes: Shallow Hole Angle, , Proceeding of ASME Turbo Expo 2012, Denmark, pp. GT2012-68215.

DOI: 10.1115/gt2012-68215