Losses in Turbine and Compressor Cascades

Chapter

Abstract

The flow through a turbomachine is generally three-dimensional, viscous, highly unsteady, transitional, turbulent, and compressible. This complex flow is associated with total pressure losses caused by different flow and geometry parameters. To accurately predict the efficiency of a turbomachine, accurate flow calculation is required. The most accurate flow calculation method is the direct numerical simulation (DNS) which solves the Navier-Stokes equations without including any turbulence and transition models. This method is currently being applied to different turbomachinery components with great success. However, for the time being, the computational efforts and the required computation time makes the application of DNS as a design tool impractical. As an alternative, the Reynolds averaged version of the Navier-Stokes equations (RANS) is routinely applied in turbomachinery design. To simulate the flow relatively accurately by RANS, the turbomachinery aerodynamicists have to choose, among a variety of turbulence and transition models, the most suitable one that satisfactorily predicts the efficiency of the turbomachine under design. Since most of these models involve empirical correlations that are derived from simple flow experiments, they deliver efficiencies that significantly differ from the measured efficiency of the machine. To find an acceptable solution, the computer Navier-Stokes codes are frequently calibrated. The issue of laminar turbulent transition, turbulence and its modeling is treated in Chapter 19 and more comprehensively in [1].

Keywords

Loss Coefficient Total Pressure Loss Vortex Filament Labyrinth Seal Boundary Layer Development 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Schobeiri, M.T.: Fluid Mechanics for Engineers. A Graduate Text Book. Springer, Heidelberg (2010)MATHCrossRefGoogle Scholar
  2. 2.
    Traupel, W.: Thermische Turbomaschinen, vol. I. Springer, New York (1977)Google Scholar
  3. 3.
    Pfeil, H.: Verlustbeiwerte von optimal ausgelegten Beschaufelungsgittern. Energie und Technik 20, Jahrgang, Heft 1, L.A. Leipzig Verlag Düsseldorf (1968)Google Scholar
  4. 4.
    Kirchberg, G., Pfeil, H.: Einfluß der Stufenkenngrössen auf die Auslegung von HD-Turbinen. Zeitschrift Konstruktion, 23. Jahrgang, Heft 6 (1971)Google Scholar
  5. 5.
    Speidel, L.: Einfluß der Oberflächenrauhigkeit auf die Strömungsverluste in ebenen Schaufelgittern. Zeitschrift Forschung auf dem Gebiete des Ingenieurwesens, vol. 20(5) (1954)Google Scholar
  6. 6.
    NASA SP-36 NASA Report (1965)Google Scholar
  7. 7.
    Prandtl, L.: Zur Berechnung von Grenzschichten. ZAMM 18, 77–82 (1938)MATHCrossRefGoogle Scholar
  8. 8.
    von Kármán, T.: Über laminare und turbulente Reibung. ZAMM 1(1921), 233–253 (1921)MATHGoogle Scholar
  9. 9.
    Ludwieg, H., Tillman, W.: Untersuchungen über die Wandschubspannung in turbulenten Reibungsschichten. Ingenieur Archiv 17, 288–299, Summary and translation in NACA-TM-12185 (1950)Google Scholar
  10. 10.
    Lieblein, S., Schwenk, F., Broderick, R.L.: Diffusions factor for estimating losses and limiting blade loadings in axial flow compressor blade elements. NACA RM E53D01 June (1953)Google Scholar
  11. 11.
    Schobeiri, M.T.: A New Shock Loss Model for Transonic and Supersonic Axial Compressors With Curved Blades. AIAA, Journal of Propulsion and Power 14(4), 470–478 (1998)CrossRefGoogle Scholar
  12. 12.
    Berg, H.: Untersuchungen über den Einfluß der Leistungszahl auf Verluste in Axialturbinen. Dissertation, Technische Hochschule Darmstadt, D 17 (1973)Google Scholar
  13. 13.
    Wolf, H.: Die Randverluste in geraden Schaufelgittern. Dissertation, Technische Universität Dresden (1960)Google Scholar
  14. 14.
    Schichting, H.: Boundary Layer Theory. McGraw-Hill series. McGraw-Hill, New York (1979)Google Scholar
  15. 15.
    Pfeil, H.: Zur Frage der Spaltverluste in labyrinthgedichteten Hochdruckstufen von Dampfturbinen. Zeitschrift Konstruktion 23(4), 140–142 (1971)Google Scholar
  16. 16.
    Prust, H.: Cold-air study of the effect on turbine stator blade aerodynamic performance of coolant ejection from various trailing-edge slot geometries. NASA-Reports I: TMX 3000 (1974)Google Scholar
  17. 17.
    Prust, H.: Cold-air study of the effect on turbine stator blade aerodynamic performance of coolant ejection from various trailing-edge slot geometries. NASA-Reports II: TMX 3190 (1975)Google Scholar
  18. 18.
    Schobeiri, T.: Einfluß der Hinterkantenausblasung auf die hinter den gekühlten Schaufeln entstehenden Mischungsverluste. Forschung im Ingenieurwesen 51(1), 25–28 (1985)CrossRefGoogle Scholar
  19. 19.
    Schobeiri, M.T.: Optimum Trailing Edge Ejection for Cooled Gas Turbine Blades. ASME Transaction, Journal of Turbo machinery 111(4), 510–514 (1989)CrossRefGoogle Scholar
  20. 20.
    Schobeiri, M.T., Pappu, K.: Optimization of Trailing Edge Ejection Mixing Losses Downstream of Cooled Turbine Blades: A theoretical and Experimental Study. ASME Transactions, Journal of Fluids Engineering, 1999 121, 118–125 (1999)CrossRefGoogle Scholar
  21. 21.
    Sieverding, C.H.: The Influence of Trailing Edge Ejection on the Base Pressure in Transonic Cascade. ASME Paper: 82-GT-50 (1982)Google Scholar
  22. 22.
    Kline, S.J., Abbot, D., Fox, R.: Optimum design of straight-wall diffusers. ASME, Journal of Basic Engineering 81, 321–331 (1959)Google Scholar
  23. 23.
    Sovran, G., Klomp, E.D.: Experimentally determined optimum geometries for rectilinear diffusers with rectangular, conical and annular cross-section. Fluid Dynamics of Internal Flow. Elsevier Publishing Co, Amsterdam (1967)Google Scholar
  24. 24.
    Schobeiri, M.T.: Theoretische und experimentelle Untersuchungen laminarer und turbulenter Strömungen in Diffusoren. Dissertation, Technische Universität Darmstadt, D17 (1979)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringTexas A&M UniversityCollege StationUSA

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