Numerical study on the flow of Bingham plastic fluids around an array of cylinders

• Published in: Materials today : proceedings 2024, Vol.111, p.78-85
• Main Authors: Gautam, Shruti, Majumder, Subhajit, Thakur, Pooja
• Format: Article
• Language: English
• Subjects: Bingham number; Bingham plastic fluids; COMSOL Multiphysics; Prandtl number; Reynolds number
• ISSN: 2214-7853; 2214-7853
• DOI: 10.1016/j.matpr.2023.11.098

The present work is focused on the study of uniformly placed array of heated circular cylinders in the Bingham plastic fluid. COMSOL Multiphysics (version 5.5) based on FEM method has been used to solve the governing continuity, energy, and momentum equations numerically for the following range of dimensionless numbers: Reynolds number 1 ≤ Re ≤ 40, Prandtl number 0.7 ≤ Pr ≤ 100 and Bingham number 0 ≤ Bn ≤ 100. Validation of the model has been done by comparing the present results with the results of Bharti et.al. For visualizing the flow field thoroughly, streamlines, shear rate and drag coefficient are plotted around the array of cylinders. However, to determine the heat transfer between the array of cylinders and fluid, detailed analysis of isotherms and average Nusselt number investigated thoroughly. The streamlines show that at low Reynolds number (Re ≤ 1) the front and rear twin vortices, at moderate Reynolds number (Re ∼ 20) only a rear twin vortex and at high Reynolds number (Re = 40) the wall vortices have been observed. The Bingham plastic fluid suppresses the vortices. The drag coefficient increases and heat transfer decreases with increasing Bingham number. It is also noticed that the main drag and heat transfer is due to the first layer of array of cylinders.