Dolusavak Akımının Farklı Türbülans Kapatma Modelleri ile Sayısal Hesabı

Öz

Laboratuvardaki bir dolusavak modelindeki akımda hızlar ve su yüzü profili ölçülmüştür. Deneyle aynı özelliklerdeki akımı idare eden temel denklemler Sonlu Hacimler yöntemi ile sayısal olarak çözülmüştür. Sayısal modellemede, Standard k-, Renormalization-group k- ve Realizable k-ε türbülans kapatma modelleri kullanılmıştır. Sayısal model bulgularının doğrulanmasına yönelik olarak deneysel bulgularla yapılan karşılaştırmalar, Renormalization-group k-ε ve Realizable k-ε türbülans modellerinden elde edilen sayısal bulguların birbirlerine çok yakın, ve her iki modelin de hız alanı ve su yüzü profilinin hesaplanmasında Standard k- modeline göre daha başarılı olduğunu göstermiştir

Anahtar Kelimeler

• Dolusavak, hız profili, VOF, Türbülans kapatma modelleri, Sayısal hesaplama

Numerical Analysis of Spillway Flow Using Different Turbulence Closure Models

Öz

Velocity field and free surface profile of flow over a spillway is measured in a laboratory channel. The governing equations are numerically solved using Finite Volume method for the flow having the same conditions with experiment. In the numerical simulation of the flow, Standard k-, Renormalization-group k-ε and Realizable k-ε turbulence closure models are employed. Experimental validations of the computations show that the numerical results from the Renormalization-group k-ε and Realizable k-ε turbulence model are very close to each other, and they are both more successful compared to the Standard k- turbulence model, in predicting the velocity field and free surface of the flow

Anahtar Kelimeler

• Spillway, Velocity field, VOF, Turbulence closure models, Numerical analysis

Kaynakça

1. 1.Kırkgöz, M.S., Aköz, M.S. ve Öner, A.A. 2008. “Experimental And Theoretical Analyses of 2D Fows Upstream of Broad-Crested Weirs”, Canadian Journal of Civil Engineering, 35(9): 975–986.
2. 2. Aköz, M.S. ve Kırkgöz, M.S. 2009. “Numerical and Experimental Analyses of the Flow Around a Horizontal Wall-Mounted Circular Cylinder”, Transactions of the Canadian Society for Mechanical Engineering, 33(2), 29-55.
3. 3. Aköz, M.S., Kırkgöz, M.S. ve Öner, A.A. 2009. “Experimental and Numerical Modeling of a Sluice Gate Flow”, Journal of Hydraulic Research. 47(2), 167-176.
4. 4. Öner A. A, Aköz M. S., Kırkgöz M. S., and Gümüş, V. 2012. “Experimental Validation of Volume of Fluid Method for a Sluice Gate Flow,” Advances in Mechanical Engineering, vol. 2012, 10.
5. 5. Soydan N. G., Aköz, M. S., Şimşek, O. ve Gümüş, V. 2012. “Trapez Kesitli Geniş Başlıklı Savak Akımının K-Ε Tabanlı Türbülans Modelleri ile Sayısal Modellenmesi”, Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, 27(2), ss. 47-58.
6. 6. Kırkgöz, M.S., Gümüş, V., Soydan, N.G., Şimşek, O. ve Aköz, M.S. 2012. “Experimental and Numerical Modeling of Flow over a Gate- Controlled Semi-Cylinder Weir”, 10th International Congress on Advances in Civil Engineering, 17-19 October, Ankara, 0184:1-10.
7. 7. Güzel, H. 1991. “Baraj Dolusavak Kanalında Enerji Kaybının İncelenmesi”, Y. Lisans Tezi, Ç.Ü. Fen Bilimleri Enstitüsü. Adana. 8. Launder B. E. ve Spalding D. B., 1972. “Lectures in Mathematical Models Ofturbulence. Academic Press”, London, England.
8. 9. Yakhot, V., Orszag, S.A., Thangam, S., Gatski, T.B. ve Speziale, C.G., 1992. “Development of Turbulence Models for Shear Flows by a Double Expansion Technique”, Physics of Fluids A, 4(7), 1510-1520.

9. 10. Shih T.H., Liou W.W., Shabbir A., Yang Z. ve Zhu J, (1995). “A New k-ε Eddy-Viscosity Model for High Reynolds Number Turbulent Flows - Model Development and Validation”, Computers Fluids, 24(3).227–238.
10. 11. Hirt, C. W. ve Nichols, B. D., 1981. “Volume of Fluid (VOF) Method for the Dynamics of Free Boundaries”, J. Comput. Phys., 39, pp., 201–225.
11. 12. Ansys Inc., 2012. Release 14.0. www.ansys.com.
12. 13. Patankar, S.V. ve Spalding, D.B., 1972. “A Calculation Procedure for Heat, Mass and Momentum Transfer in Three-Dimensional Parabolic Flows”, International Journal of Heat and Mass Transfer, 15, 1787-1806.
13. 14. Patankar, S.V., 1980. Numerical Heat Transfer and Fluid Flow, Hemisphere, Washington.
14. 15. Chen, H.C. ve Patel, V.C., 1988. “Near-Wall Turbulence Models for Complex Flows Including Separation”, AIAA journal, 26(6), 641-648.
15. 16. Roache, P.J., 1998. “ Verification of Codes and Calculations”, AIAA Journal, 36(5), 696- 702.
16. 17. Çelik, İ.B., Ghia, U., Roache, P.J., Freitas, C.J., Coleman, H. ve Raad, P.E., 2008. “Procedure for Estimation and Reporting of Uncertainty Due to Discretization in CFD applications”, ASME Journal of Fluids Engineering, 130(1), 1-4.
17. 18. Kırkgöz, M.S. ve Ardıçlıoğlu, M., 1997. “Velocity Profiles of Developing and Developed Open Channel Flow”, Journal of Hydraulic Engineering, 123(12), 1099-1105.