Faculty Publications
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Item Lattice Boltzmann computation of multiple solutions in a double-sided square and rectangular cavity flows(Elsevier Ltd, 2018) Arumuga Perumal, D.A.This paper uses Lattice Boltzmann computation to obtain multiple fluid flow solutions in square and rectangular cavity that involves movement of the facing and non-facing walls. For some aspect ratios the double-sided lid-driven cavity problem has multiple steady fluid flow solutions. In double-sided rectangular cavities, a single-relaxation-time model is used to over out Lattice Boltzmann computations in order to receive multiple fluid flow solutions. Three numerical examples are taken into consideration on this work. First one is double-sided square cavity with parallel wall movement, double-sided non-facing rectangular lid-driven cavity with parallel wall movement and the final one is the double-sided lid-driven rectangular cavity with antiparallel wall movement. When the walls move in pairs, multiple fluid flow solutions exist above critical Reynolds numbers. In the present work, five multiple solutions of parallel wall movement and seven multiple solutions of antiparallel wall movement is acquired. The boundary conditions used are stable and also correct. It might be inferred that the present mesoscopic Lattice Boltzmann study produces comes about that are in phenomenal similarity with prior customary numerical perceptions. © 2017Item Computation of fluid flow in double sided cross-shaped lid-driven cavities using Lattice Boltzmann method(Elsevier Ltd, 2018) Bhopalam, S.B.; Arumuga Perumal, D.A.; Yadav, A.K.This work implements Lattice Boltzmann method to compute flows in double-sided cross-shaped lid-driven cavities. Firstly, a complicated geometry which is a symmetrized version of the staggered lid-driven cavity namely, the double-sided cross-shaped lid-driven cavity with antiparallel uniform wall motion is studied employing Single as well as Two Relaxation time models. The streamline patterns and vorticity contours obtained for low to moderate Reynolds numbers (150–1000) are compared with published results and found to be in good accordance. Next, this code is extended to simulate flows in a double-sided cross-shaped lid-driven cavity with parallel uniform wall motion. The effect of three dimensionality is also studied for low Reynolds numbers. Lattice Boltzmann method is then used to investigate the oscillating double-sided cross-shaped lid-driven cavity with antiparallel and parallel wall motions. The movement and formation of primary and secondary vortices have been well captured with the variation of Reynolds numbers and oscillating frequencies for uniform and oscillating wall motions. Reasonable agreements with the established results have been observed for the double-sided cross-shaped cavity with uniform wall motions, while new results have been obtained in the case of oscillating wall motions. © 2018 Elsevier Masson SASItem Numerical analysis of fluid flows in L-Shaped cavities using Lattice Boltzmann method(Elsevier Ltd, 2020) Bhopalam, S.R.; Arumuga Perumal, D.A.The current study explores the Two-Relaxation Time (TRT) model of lattice Boltzmann method to compute incompressible flows in L-shaped cavities. Numerical code validation of the developed code with previous results has been initially established. After establishing the credibility of the developed code, the flow characteristics in L-shaped cavities have been studied in detail by considering two kinds of wall motions: single-sided and two-sided (with parallel and anti-parallel wall motions). Additionally, Reynolds numbers and aspect ratios of the cavity are also appropriately changed to study the effects of these parameters on the flow characteristics. The inclusion of a corner in the L-shaped cavity has been found to result in interesting flow topologies, characterized by the presence of primary, secondary and wall eddies. Current numerical simulations reveal the centreline velocity profiles, flow structure and formation of vortices generated in L-shaped cavities to resemble the flow characteristics observed in deep cavities. © 2020 The AuthorsItem Computational appraisal of fluid flow behavior in two-sided oscillating lid-driven cavities(Elsevier Ltd, 2021) Bhopalam, S.R.; Arumuga Perumal, D.A.; Yadav, A.K.The current work employs lattice Boltzmann simulations to compute incompressible flows in two-sided oscillating lid-driven cavities. Vortex dynamics in oscillatory lid-driven cavity flows is more complex than steady lid-driven cavity flows due to the strong dependence of the evolutionary flow field on several parameters of interest: Reynolds number (Re), dimensionless oscillating frequency (?) and Speed Ratio (SR), to name a few. A comprehensive study on the variation of flow patterns in both antiparallel and parallel oscillating wall motions has been performed by systematically varying the parameters (Re, ? and SR) over a wide range of values. To make it easier for the reader, these flow patterns have been appropriately classified into several flow modes, which are later explained using streamline patterns, centerline velocity profiles and three-dimensional flow maps. Simulations show that Re and ? control the penetration depth of the fluid inside the cavity, while SR controls the size and strength of additional primary or corner vortices generated from the bottom lid motion. The significance of the current work may be found in industrial applications, where Re, ? and SR may have to appropriately tuned to yield a specific flow mode. © 2021 Elsevier LtdItem Performance evaluation of partially filled high porosity metal foam configurations in a pipe(Elsevier Ltd, 2021) Jadhav, P.H.; Gnanasekaran, N.; Arumuga Perumal, D.A.; Mobedi, M.In this contemporary research, a parametric analysis of partially filled high porosity metallic foams in a horizontal conduit is performed to augment heat transfer with reasonable pressure drop. The investigation includes six different models filled partly with aluminium foam by varying internal diameter of foams from the wall side and external diameter of foam from the core of the tube. The pore density of the foam ranges from 10 to 45 PPI and their porosity varies from 0.90 to 0.95. Flow dynamics are captured using Darcy Extended Forchheimer model for the porous filled region and two-equation turbulence k-? model employed in clear region of the fluid. The local thermal non-equilibrium assumption is incorporated in porous filled region of the conduit to compute the heat transport characteristics. The results showed that the thermal performance factor of 10 PPI aluminium foam performs close to the 10 PPI expensive copper foam. The performance factor is found to be higher for 30 PPI aluminium foam amongst the PPI's of the foam considered. However, the performance factor is found to be 2.93, 2.22 and 1.73 for 30PPI, 45 PPI and 20PPI with their porosities of 0.92, 0.90 and 0.90, respectively for the model 1, model 2 and model 3 at lower Reynolds number of 4500 and then it decreases progressively with increasing flow rates of the fluid. The results of average wall temperature, average Nusselt number and Colburn j factor are also evaluated to obtain best possible performance. © 2021Item Numerical Analysis of Lid-Driven Cavity Flow Induced by Triangular Obstacles †(Multidisciplinary Digital Publishing Institute (MDPI), 2023) Hegde, S.N.; Bendre, N.L.; Arumuga Perumal, D.A.This research work presents a study on the flow behaviour in the lid-driven cavity (LDC) flows with triangular blocks using computational fluid dynamics techniques. The LDC flow is a widely studied problem that remains a standard for viscous incompressible fluid flows, with a range of parameters, including the Reynolds number, being explored. The finite volume method was used to discretize the domain, and simulations were computed using ANSYS FLUENT 2021 R1. The fluid flow started when the top wall is moved in the +X direction, whereas the other three walls are kept stationary. A grid independence test was performed to determine the optimum grid size and to obtain a grid-independent solution. Quantitative elements of the 2D flows in lid-driven cavities were explored for Reynolds numbers ranging from 1000 to 8000, and the results were validated against the existing literature. The consequence of different values of the Reynolds number (Re) were analyzed and examined through vorticity, streamline patterns, and kinetic energy contours. The velocity profile at the centerline was enhanced, and the vortex number and size increased with an increase in Re. The behaviour of the isolines of the vortices and the kinetic energy contours was also analyzed. The kinetic energy contours show that the high velocity of the fluid particles close to the upper wall is a significant factor affecting the maximum kinetic energy values. As the Reynolds number increased, the kinetic energy gradually increased at the boundary. This suggests that the Re considerably affects the energy values. Overall, this study provides valuable insights into the flow behaviour of lid-driven cavities and the effects of obstacles on flow patterns, contributing to the existing literature and being useful for researchers and engineers working in the field of fluid dynamics. © 2023 by the authors.Item Integrated microchannel cooling for densely packed electronic components using vanadium pentaoxide (V2O5)-xerogel nanoplatelets-based nanofluids(Springer Science and Business Media B.V., 2023) Narendran, G.; Gnanasekaran, N.; Arumuga Perumal, D.A.; Moolayadukkam, M.; Nagaraja, H.S.The present study reports the implementation of novel nanoplatelets-based vanadium pent oxide (V2O5)-xerogel for the application of conjugate cooling in densely packed electronic devices. An integrated heat sink is made up of copper with a channel width of 490 µm and is shrink-fitted into aluminium block that acts as a heat spreader. V2O5-xerogel is synthesized by melt quenching process and characterized based on field emission scanning electron microscope, transmission electron microscope, and X-ray diffraction to analyse the surface morphology of the particles. Studies related to the stability of the nanofluids for different concentrations are discussed in this paper. Furthermore, a study on the effect of pulsating flow in microchannel is performed for different flow rates. As a result, a maximum enhancement of 17% in heat transfer coefficient was observed for the concentration of 0.4 mass% with a flow rate of 200 mL min-1 compared to a pure fluid. Finally, the results reveal that the xerogel is a potential working fluid for heat transfer applications involving microscale devices. © 2023, Akadémiai Kiadó, Budapest, Hungary.Item Simulation of fluid flow in a lid-driven cavity with different wave lengths corrugated walls using Lattice Boltzmann method(Taiwan Institute of Chemical Engineers, 2023) Fatima, N.; Rajan, I.; Arumuga Perumal, D.A.; Anbalagan, A.; Ahmed, S.A.A.; Gorji, M.R.; Ahmad, Z.Background: The Lid-driven cavity (LDC) flow is an interesting problem in fluid mechanics. The lattice Boltzmann Method (LBM) is used to simulate fluid flow in a LDC with different wave lengths corrugated walls. Methods: The D2Q9 model is used for the 2D bounded domain where the analysis of bottom-bounded wall corrugations on the flow features is analyzed. For validation, a square corrugation along the bottom wall with a driven top wall is considered. A lattice size independence study is performed and the LBM code is substantiated with published results for different values of Reynolds number. The code is then modified by using sinusoidal corrugated walls with different wavelengths along the bottom surface. Significant finding: The streamline patterns, vorticity contours and kinetic energy contours are studied for different Reynolds number. Results shown that the position, number and size of vortices depend on the number of corrugations and value of Reynolds number used. The secondary vortices tend to increase in size as the Reynolds number increase. The kinetic energy contours show maximum energy near the top wall which reduces inside the cavity. © 2023Item Three-dimensional simulations of fluid flows in oscillating lid-driven cavities using lattice Boltzmann method(Institute of Physics, 2023) Bhopalam, S.R.; Arumuga Perumal, D.A.; Yadav, A.K.We utilize the lattice Boltzmann method to conduct three-dimensional simulations of incompressible flows in oscillating cubic lid-driven cavities. Our investigation focuses on examining the impact of Reynolds number and oscillating frequency on the flow field. Notably, we observe that the flow field can be adequately approximated as two-dimensional within the low and intermediate Reynolds number range, but this approximation is no longer valid for high Reynolds numbers. Additionally, we find that high Reynolds numbers correspond to transient flow fields, while low and moderate Reynolds numbers exhibit quasi-steady periodic flow fields. Our study holds significant relevance for industrial processing applications, where the Reynolds numbers and oscillating frequencies can be optimized to achieve a desired flow field. © 2023 The Japan Society of Fluid Mechanics and IOP Publishing Ltd.