Faculty Publications

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    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 SAS
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    Fluid flow characteristics in double-sided lid-driven microcavity using lattice boltzmann method
    (Begell House Inc. orders@begellhouse.com, 2019) Rajan, I.; Arumuga Perumal, D.A.; Yadav, A.K.
    In this study, we analyze the fluid flow characteristic of rarefied gas flows in double-sided lid-driven microcavity subjected to various combinations of boundary conditions that simulate the slip at the walls using lattice Boltzmann method (LBM) constituting a single relaxation time (SRT) model. The fluid motion inside a closed square container with two rigid walls and two moving walls constitutes an exemplar for internal vortex flows. First, a complicated geometry, namely, the single-sided lid-driven microcavity is studied using the LBM-SRT model. Next, this code is extended to simulate flows in a double-sided microcavity flow. Numerical computation of fluid flow incorporating various slip boundary conditions as bounce-back and specular boundary condition (BSBC) for different values of tangential accommodation momentum coefficient (TMAC) has been investigated. Various values of Knudsen number in the slip and transition regime (Kn = 0.01, 0.05, 0.10, 0.135, and 0.15) along with different aspect ratios of 0.33, 0.50, 1.0, 2.0, and 3.0 have been considered in this study. The streamline patterns and velocity profiles were obtained for different Knudsen numbers. The formation and movement of primary vortices have been well captured with the variation of Knudsen numbers for different aspect ratios of microcavity. © 2019 by Begell House, Inc.
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    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 Ltd
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    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.