KARE SİLİNDİR ÜZERİNDEN LAMİNER SÜREKLİ AKIŞTA BLOKAJ ORANININ ISI TRANSFERİ VE AKIŞ KARAKTERİSTİKLERİNE ETKİSİNİN SAYISAL OLARAK İNCELENMESİ

Yıl 2020, , 379 - 390, 30.04.2020

Mehmet Özgün Korukçu

https://doi.org/10.17482/uumfd.630535

Öz

Sınırlandırılmış bir kanal içerisinde yer alan tek kare silindir (KS) üzerinden iki boyutlu laminer sürekli akış için blokaj (=B/H) oranının ısı transferi ve akış karakteristiklerine olan etkisi incelenmiştir. Çalışmada Reynolds sayısı Re=40 değerinde sabit tutulurken blokaj oranı =0.125-0.8 değerleri arasında değiştirilmiştir. Hesaplamalarda ANSYS CFX 14.0 kullanılmıştır. Blokaj oranı etkisinin KS yüzeyleri üzerindeki sürükleme katsayısı (Cd), sürtünme katsayısı (Cf), boyutsuz yeniden birleşme uzunluğu (Lr/B) ve ortalama Nusselt sayısı (Nu) üzerine olan etkileri incelenmiştir. Blokaj oranı arttıkça sürükleme katsayısı (Cd), sürtünme katsayısı (Cf) ve ortalama Nusselt sayısı (Nu) değerlerinin arttığı ancak boyutsuz yeniden birleşme uzunluğu (Lr/B) değerinin azaldığı bulunmuştur. Sürükleme katsayısı (Cd), sürtünme faktörü (Cf), boyutsuz yeniden birleşme uzunluğu (Lr/B) ve ortalama Nusselt sayısı değerlerinin blokaj oranına göre değişimini veren bağıntılar elde edilmiştir.

Anahtar Kelimeler

Sınırlandırılmış Akış, Kare Silindir, Akış Karakteristikleri, Isı Transferi, HAD

Destekleyen Kurum

BURSA ULUDAĞ ÜNİVERSİTESİ BİLİMSEL ARAŞTIRMA PROJELERİ BİRİMİ

Proje Numarası

KUAP-MH(2014)/15

Teşekkür

Bu çalışmanın KUAP-MH(2014)/15 sayılı proje ile gerçekleşmesini sağlayan Bursa Uludağ Üniversitesi Bilimsel Araştırma Projeleri Birimi’ne teşekkür ederim.

EFFECT OF BLOCKAGE RATIO ON HEAT TRANSFER AND FLOW CHARACTERISTICS OF LAMINAR STEADY FLOW OVER SQUARE CYLINDER

Öz

Effect of blockage ratio (=B/H) on heat transfer and flow characteristics are investigated for two-dimensional laminar steady flow over a square cylinder (SC) in a confined channel. In the study, while Reynolds number held at Re=40, blockage ratio is changed between =0.125-0.8 values. For numerical calculations, ANSYS CFX 14.0 is used. Effect of blockage ratio on drag coefficient (Cd), friction factor (Cf), dimensionless recirculation length (Lr/B) and average Nusselt number (Nu) values on SC surfaces are investigated. It is found that as the blockage ratio increases drag coefficient (Cd), friction coefficient (Cf), and average Nusselt number (Nu) values increase, but dimensionless recirculation length (Lr/B) values decrease. Equations of drag coefficient (Cd), friction coefficient (Cf), dimensionless recirculation length (Lr/B), and average Nusselt number variation respect to blockage ratio are derived. 

Anahtar Kelimeler

Confined Flow, Square Cylinder, flow characteristics, heat transfer, CFD

Proje Numarası

KUAP-MH(2014)/15

Kaynakça

• 1. Berrone, S., V. Garbero, and M. Marro. 2011. “Numerical Simulation of Low-Reynolds Number Flows Past Rectangular Cylinders Based on Adaptive Finite Element and Finite Volume Methods.” Computers and Fluids 40 (1): 92–112. doi.org/10.1016/j.compfluid.2010.08.014.
• 2. Bhattacharyya, S., and S. Dhinakaran. 2008. “Vortex Shedding in Shear Flow Past Tandem Square Cylinders in the Vicinity of a Plane Wall.” Journal of Fluids and Structures 24 (3): 400–417. doi.org/10.1016/j.jfluidstructs.2007.09.002.
• 3. Bouaziz, Mohamed, Sameh Kessentini, and Saïd Turki. 2010. “Numerical Prediction of Flow and Heat Transfer of Power-Law Fluids in a Plane Channel with a Built-in Heated Square Cylinder.” International Journal of Heat and Mass Transfer 53 (23–24): 5420–29. doi.org/10.1016/j.ijheatmasstransfer.2010.07.014.
• 4. Breuer, M., J. Bernsdorf, T. Zeiser, and F. Durst. 2000. “Accurate Computations of the Laminar Flow Past a Square Cylinder Based on Two Different Methods: Lattice-Boltzmann and Finite-Volume.” International Journal of Heat and Fluid Flow 21 (2): 186–96. doi.org/10.1016/S0142-727X(99)00081-8.
• 5. Chatterjee, Dipankar, and Bittagopal Mondal. 2011. “Effect of Thermal Buoyancy on Vortex Shedding behind a Square Cylinder in Cross Flow at Low Reynolds Numbers.” International Journal of Heat and Mass Transfer 54 (25–26): 5262–74. doi.org/10.1016/j.ijheatmasstransfer.2011.08.016.
• 6. Cheng, M., D. S. Whyte, and J. Lou. 2007. “Numerical Simulation of Flow around a Square Cylinder in Uniform-Shear Flow.” Journal of Fluids and Structures 23 (2): 207–26. doi.org/10.1016/j.jfluidstructs.2006.08.011.
• 7. Dhiman, A. K., R. P. Chhabra, and V. Eswaran. 2005. “Flow and Heat Transfer across a Confined Square Cylinder in the Steady Flow Regime: Effect of Peclet Number.” International Journal of Heat and Mass Transfer 48 (21–22): 4598–4614. doi.org/10.1016/j.ijheatmasstransfer.2005.04.033.
• 8. Dhiman, A. K., R. P. Chhabra, and V. Eswaran. 2008. “Steady Flow across a Confined Square Cylinder: Effects of Power-Law Index and Blockage Ratio.” Journal of Non-Newtonian Fluid Mechanics 148 (1–3): 141–50. doi.org/10.1016/j.jnnfm.2007.04.010
• 9. Dhiman, Amit Kumar. 2009. “Heat Transfer to Power-Law Dilatant Fluids in a Channel with a Built-in Square Cylinder.” International Journal of Thermal Sciences 48 (8): 1552–63. doi.org/10.1016/j.ijthermalsci.2008.12.013.
• 10. Kim, Do Hyeong, Kyung Soo Yang, and Mamoru Senda. 2004. “Large Eddy Simulation of Turbulent Flow Past a Square Cylinder Confined in a Channel.” Computers and Fluids 33 (1): 81–96. doi.org/10.1016/S0045-7930(03)00040-9.
• 11. Mahir, Necati. 2009. “Three-Dimensional Flow around a Square Cylinder near a Wall.” Ocean Engineering 36 (5): 357–67. doi.org/10.1016/j.oceaneng.2009.01.002.
• 12. Malekzadeh, S., and A. Sohankar. 2012. “Reduction of Fluid Forces and Heat Transfer on a Square Cylinder in a Laminar Flow Regime Using a Control Plate.” International Journal of Heat and Fluid Flow 34: 15–27. doi.org/10.1016/j.ijheatfluidflow.2011.12.008.
• 13. Ozgoren, Muammer. 2006. “Flow Structure in the Downstream of Square and Circular Cylinders.” Flow Measurement and Instrumentation 17 (4): 225–35. doi.org/10.1016/j.flowmeasinst.2005.11.005.
• 14. Paliwal, B., Atul Sharma, R. P. Chhabra, and V. Eswaran. 2003. “Power Law Fluid Flow Past a Square Cylinder: Momentum and Heat Transfer Characteristics.” Chemical Engineering Science 58 (23–24): 5315–29. doi.org/10.1016/j.ces.2003.09.010.
• 15. Sharma, Atul, and V. Eswaran. 2004. “Heat and Fluid Flow across a Square Cylinder in the Two-Dimensional Laminar Flow Regime.” Numerical Heat Transfer; Part A: Applications 45 (3): 247–69. doi.org/10.1080/10407780490278562.
• 16. Sheard, Gregory J. 2011. “Wake Stability Features behind a Square Cylinder: Focus on Small Incidence Angles.” Journal of Fluids and Structures 27 (5–6): 734–42. doi.org/10.1016/j.jfluidstructs.2011.02.005.
• 17. Song, Chi Su, and Seung O. Park. 2009. “Numerical Simulation of Flow Past a Square Cylinder Using Partially-Averaged Navier-Stokes Model.” Journal of Wind Engineering and Industrial Aerodynamics 97 (1): 37–47. doi.org/10.1016/j.jweia.2008.11.004.
• 18. Turki, Said, Hassen Abbassi, and Sassi Ben Nasrallah. 2003. “Two-Dimensional Laminar Fluid Flow and Heat Transfer in a Channel with a Built-in Heated Square Cylinder.” International Journal of Thermal Sciences 42 (12): 1105–13. doi.org/10.1016/S1290-0729(03)00091-7.