Abstract
Forced convection heat transfer due to airflow across an array of thin disks is encountered in various engineering applications. In this work, a three-dimensional steady Reynolds-Averaged Navier-Stokes computational fluid dynamics (CFD) simulation is performed to investigate the phenomenon at the surfaces of an array of disks. A computational grid comprising of a solid domain representing the array of disks and a fluid domain denoting the airflow is set up. A two-step solution procedure is employed whereby first the airflow across the disks is simulated till convergence and then the heat transfer is calculated. The temperature of the air before the array of disks, that of each surface of the disks, and the wall heat flux are monitored to calculate average convective heat transfer coefficients (CHTCs). The CFD model is validated using a wind tunnel experiment and it is shown that both are in close agreement with each other based on the surface temperatures and average CHTC predictions. The CHTCs are found to be significantly higher on the upwind face of the disks compared to the downwind side. Finally, based on the simulations, a correlation based on the non-dimensional average Nusselt number versus Reynolds and Prandtl numbers is derived.
Acknowledgements
The Interfaculty Council for Development Co-operation (IRO), and the VLIR-UOS through the grant number SI-2020-01-90 are gratefully acknowledged for the financial support. In addition, we like to acknowledge Winok van Tendeloo and Lore Arnauts for providing the measurement data.
Additional information
Notes on contributors
Petros Demissie Tegenaw
Petros Demissie Tegenaw obtained a MSc in electromechanical engineering from KU Leuven, Belgium in 2016. He taught various mechanical engineering courses in Addis Ababa Science and Technology University, Ethiopia in 2016–2017. He was awarded a scholarship from KU Leuven for a PhD in mechanical engineering starting from late 2017. Currently, he is working on a PhD research project to predict and validate conjugate heat and mass transfer phenomena using advanced computational fluid dynamics.
Ashmore Mawire
Ashmore Mawire holds a PhD degree in Applied Physics from the North-West University in South Africa which he obtained in 2010. He is a Professor in the Department of Physics and Electronics at the North-West University. He is the principal researcher in the solar thermal group of the Material Science Innovation and Modeling focus area. His research interests include electronic instrumentation, renewable energy systems, heat transfer and solar thermal energy storage technology. He has published over 30 high impact factor ISI journal articles and presented papers at over 30 peer reviewed international conferences. His articles are mainly focused on domestic solar thermal energy storage applications.
Pieter Verboven
Pieter Verboven holds a PhD in Applied Biological Sciences from het University of Leuven (KU Leuven) in Belgium. He currently is Industrial Research Manager at the same university in the division of Mechatronics, Biostatistics and Sensors (MeBioS). He is head of a research group on computer-aided design and engineering of agrofood processes. He promoted 15 PhD theses over the last 10 years. He has more than 200 publications in international peer-reviewed journals, 8 chapters in books and +2200 citations. His h-index is 39. He is a member of the editorial advisory board of the Journal of Food Engineering and Postharvest Biology and Technology. He coordinates the platform CADcracker for technology transfer to the agrofood industry.
Maarten Vanierschot
Maarten Vanierschot obtained a MSc in Mechanical Engineering from the KU Leuven in July 2002 and received his PhD at the same institution in 2007. After being a postdoctoral researcher for two years, he became an assistant professor in 2009 at campus Group T of the KU Leuven. In 2019, he became associate professor. His research activities include, amongst others: fluid flow simulations using computational fluid dynamics, fluid flow measurements using advanced measurement techniques and fluid flow modeling using low order model extraction. He has published 89 papers in international peer reviewed journals or peer reviewed conferences. He is/was involved in the coordination of over 34 research projects, including several bilateral industrial projects.