Suscripción a Biblioteca: Guest
Página principal de la Biblioteca Digital de ICHMT Año actual Archivos Comité Ejecutivo Centro Internacional de Transferencia de Calor y Masa

Roughness effects on separated and reattached open channel turbulent flow

DOI: 10.1615/ICHMT.2012.ProcSevIntSympTurbHeatTransfPal.1810
pages 1770-1781

Afua A. Ampadu-Mintah
Department of Mechanical and Manufacturing Engineering, University of Manitoba, Winnipeg, MB, R3T 5 V6, Canada

Mark F. Tachie
Department of Mechanical and Manufacturing Engineering, University of Manitoba, Winnipeg MB, R3T 5V6 Canada

Martin Agelin-Chaab
Automotive, Mechanical and Manufacturing Engineering Department, University of Ontario Institute of Technology Oshawa, ON, L1H 7K4, Canada


An experimental study was undertaken to investigate the effects of surface roughness on the mean velocity and higher order turbulence statistics in separated and reattached open channel turbulent flows downstream of a backward facing step (BFS). The BFS was kept hydraulically smooth but the floor downstream of the step was covered with two different roughness elements. In addition to these two rough surfaces, a reference smooth surface was also studied to facilitate the interpretation of roughness effects on the flow characteristics. The depth of the approach open channel flow, the approach freestream velocity and Reynolds number were kept approximately constant for each of the experiments at 66 mm, 0.3 m/s and 19800 respectively to ensure that the boundary layer characteristics of the approach flow are similar in all the three test cases. The results showed that surface roughness significantly reduced reattachment length and turbulence level in the separated region. Two point correlation analyses indicated that in the separated region there is similarity between the smooth wall and the rough wall in the near wall region but in the redevelopment region the data for the smooth wall is more correlated than the rough wall in the near wall region.

ICHMT Digital Library

Bow shocks on a jet-like solid body shape. Thermal Sciences 2004, 2004. Pulsed, supersonic fuel jets - their characteristics and potential for improved diesel engine injection. PULSED, SUPERSONIC FUEL JETS - THEIR CHARACTERISTICS AND POTENTIAL FOR IMPROVED DIESEL ENGINE INJECTION
View of engine compartment components (left). Plots of temperature distributions in centreplane, forward of engine (right). CHT-04 - Advances in Computational Heat Transfer III, 2004. Devel... DEVELOPMENT AND CURRENT STATUS OF INDUSTRIAL THERMOFLUIDS CFD ANALYSIS
Pratt & Whitney's F-135 Joint Strike Fighter Engine under test in Florida is a 3600F class jet engine. TURBINE-09, 2009. Turbine airfoil leading edge stagnation aerodynamics and heat transfe... TURBINE AIRFOIL LEADING EDGE STAGNATION AERODYNAMICS AND HEAT TRANSFER - A REVIEW
Refractive index reconstructed field. (a) Second iteration. (b) Fourth iteration. Radiative Transfer - VI, 2010. Theoretical development for refractive index reconstruction from a radiative ... THEORETICAL DEVELOPMENT FOR REFRACTIVE INDEX RECONSTRUCTION FROM A RADIATIVE TRANSFER EQUATION-BASED ALGORITHM
Two inclusion test, four collimated sources. Radiative Transfer - VI, 2010. New developments in frequency domain optical tomography. Part II. Application with a L-BFGS associated to an inexa... NEW DEVELOPMENTS IN FREQUENCY DOMAIN OPTICAL TOMOGRAPHY. PART II. APPLICATION WITH A L-BFGS ASSOCIATED TO AN INEXACT LINE SEARCH