Double-Diffusive Natural Convection in L-Shaped Cavity by Lattice Boltzmann Method: Numerical Study

Abstract

The double diffusive natural convection is studied numerically on an L-shaped cavity using lattice Boltzmann method (LBM). The top and right side of the cavity is insulated, the left and the bottom side of the cavity are maintained at high temperature, and remaining sides are considered as cold wall. This study is carried out using a two-dimensional nine-directional (D2Q9) lattice structure. Single relaxation time model is adopted to solve the LBM equations. The effects of different Rayleigh numbers (Ra = 10³–10⁵), aspect ratio (0.2–0.8), Prandtl number (Pr = 0.054, 0.7, 6.2, and 50), Lewis number (2), and buoyancy ratio (−2) on the temperature, concentration, and streamline contours are presented. For the selected range of operating parameters in this study, the heat and mass transfer are more pronounced for horizontal wall than vertical. At low Pr, the difference between horizontal wall to vertical wall average Nusselt number (Nu) is 11.2% and when Pr = 50, the same difference in average Nu is 37.5%. Similarly, the average Sherwood number between horizontal and vertical wall differences are 19.5% and 31.7%. For Ra = 10⁵, the convection rate reduced by 46% and mass diffusion reduced by 52% between Pr = 0.054–50.

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Additional information

Notes on contributors

Parthasarathy Rajesh Kanna

Parthasarathy Rajesh Kanna is a Professor in the CO₂ Research and Green Technologies Research center, Vellore Institute of Technology Vellore, India. He received his PhD from Indian Institute of Technology Guwahati, India in 2006. He has coauthored more than 90 international publications including refereed journals and conferences. He received his D.Sc. degree from Cracow University of Technology, Poland in 2015.

Anbalagan Satheesh

Anbalagan Satheesh is a Professor in the Department of Thermal and Energy Engineering, School of Mechanical Engineering, Vellore Institute of Technology, Vellore. He has completed PhD at Indian Institute of Technology Guwahati in Fluid Stream Thermal Engineering in 2011. He has been actively involved in Erasmus + capacity building project in collaboration with European Universities. His research area includes CFD applications in hydrogen storage and heat transfer.

Senthil Kumar Arumugam

Senthil Kumar Arumugam is a Professor in the School of Mechanical Engineering, VIT Bhopal University, Indian. He obtained his doctoral degree from Indian Institute of Science, Bangalore in the field of Cryogenics. He carried out his post-doctoral research in the field of Sub-millimeter gravitational force at Washington University in St. Louis, USA. His research interests include cryogenic heat pipes, CFD analysis of steam turbine exhaust-hood, transcritical CO₂ refrigeration, and solid hydrogen extrusion. He has successfully handled three funded research projects and six consultancy projects.

Hakan Fehmi Öztop

Hakan F. Oztop is an Associate Professor at Department of Mechanical Engineering, Technology Faculty, Firat University, Elazig, Turkey. He had been in Ecole Poyltechnique de Montreal, Canada in 2002 and Auburn University, USA, as a visiting scholar in 2004. He received scholarship from Turkish Research Council and NATO for post-doctorate positions. He has published more than 600 papers in SCI journals and more than 100 research papers in international or national conferences and national journals. His h-index is 87.

Neelamegam Rajan Devi

Devi Neelamegam Rajan is an Assistant Professor, Department of Physics, Auxilium College, Vellore. She received her PhD from Anna University Chennai in 2016 and Master of Philosophy from Madurai Kamaraj University, Madurai in 2007. She has completed PG and UG degrees from Fatima College, Madurai during 2006 and 2004, respectively. Her research areas are hydrogen storage, nanomaterials synthesis and characterization for heat transfer applications.