Evolution of turbulence characteristics from straight to curved pipes

Noorani A, El Khoury GK, Schlatter P (2013)

Publication Type: Journal article

Publication year: 2013

Journal

International Journal of Heat and Fluid Flow Elsevier

Book Volume: 41

Pages Range: 16-26

DOI: 10.1016/j.ijheatfluidflow.2013.03.005

Abstract

Fully developed, statistically steady turbulent flow in straight and curved pipes at moderate Reynolds numbers is studied in detail using direct numerical simulations (DNS) based on a spectral element discretisation. After the validation of data and setup against existing DNS results, a comparative study of turbulent characteristics at different bulk Reynolds numbers Reb = 5300 and 11,700, and various curvature parameters κ = 0, 0.01, 0.1 is presented. In particular, complete Reynolds-stress budgets are reported for the first time. Instantaneous visualisations reveal partial relaminarisation along the inner surface of the curved pipe at the highest curvature, whereas developed turbulence is always maintained at the outer side. The mean flow shows asymmetry in the axial velocity profile and distinct Dean vortices as secondary motions. For strong curvature a distinct bulge appears close to the pipe centre, which has previously been observed in laminar and transitional curved pipes at lower Reb only. On the other hand, mild curvature allows the interesting observation of a friction factor which is lower than in a straight pipe for the same flow rate. All statistical data, including mean profile, fluctuations and the Reynolds-stress budgets, is available for development and validation of turbulence models in curved geometries. © 2013 Elsevier Inc.

Authors with CRIS profile

Philipp Schlatter

Involved external institutions

Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH)

Sweden (SE)

How to cite

APA:

Noorani, A., El Khoury, G.K., & Schlatter, P. (2013). Evolution of turbulence characteristics from straight to curved pipes. International Journal of Heat and Fluid Flow, 41, 16-26. https://doi.org/10.1016/j.ijheatfluidflow.2013.03.005

MLA:

Noorani, A., G. K. El Khoury, and Philipp Schlatter. "Evolution of turbulence characteristics from straight to curved pipes." International Journal of Heat and Fluid Flow 41 (2013): 16-26.

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