Faculty Publications
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Item Lattice boltzmann simulation of double-sided deep cavities at low reynolds number(Pleiades journals, 2019) Kesana, B.; Shetty, V.V.; Arumuga Perumal, D.A.Lattice Boltzmann method (LBM) has been created as an option computational technique conversely with conventional computational fluid dynamics (CFD) strategies. In the present work, the fluid flow of the two-dimensional low Reynolds number flow in a rectangular cavity with two opposite moving lids and different aspect ratios (depth-to-width ratios) is examined using LBM. The impacts of aspect ratio shifting from 1.2 to 10 on vortex structure in the cavity were watched. The streamline patterns were displayed in detail. As the perspective proportion is steadily expanded from 1.2, the stream structure creates the longitudinal way of the cavity and the quantity of vortices step by step increments with the expanding viewpoint proportion. The advancement of bigger external vortices is from the centre of the cavity and observed stream patterns were symmetric about the cavity centre at various proportion. © Springer Nature Singapore Pte Ltd. 2019.Item Lattice Boltzmann computation of two dimensional differentailly heated cavity of incompressible fluid with different aspect ratios(Institute of Electrical and Electronics Engineers Inc., 2017) Karki, P.; Yadav, A.K.; Arumuga Perumal, D.A.Lattice Boltzmann Method (LBM) is a novel computational technique to solve fluid flow problem in bounded domain. Continuum based methods are being widely used to solve the natural convection problem, whereas in the last two decades, mesoscopic approach has gained popularity to solve heat transfer and fluid flow problems. In natural convection cavity, density difference caused by heating and cooling of fluid at different locations gives rise to buoyancy force which in turn drives the fluid flow. The right side and left side wall of the cavity is made hot and cold respectively whereas top and bottom walls are made adiabatic. In the present work, natural convection problem of differently heated cavity with constant Prandtl number (Pr = 0.71) and varying Rayleigh number (Ra =103-106) is solved employing LBM to study the effect of various aspect ratios (H/L) on both Nusselt number and streamlines. Results are plotted in the form of streamlines and isotherms for different Rayleigh numbers at different aspect ratios. Nusselt numbers are obtained at the hot wall and cold wall to study the rate of heat transfer. Obtained results are compared with the existing results. It is found that with increase of Rayleigh number, there is increase in the Nusselt number. The increment in aspect ratio leads to the significant decrement in the Nusselt number and vice versa. © 2017 IEEE.Item LBM combined with LM algorithm to estimate the unknown heat flux - A new inverse approach(Elsevier Ltd, 2019) Kumar, D.; Arumuga Perumal, D.A.; Gnanasekaran, N.; Kumar, M.K.The objective of the present work is the application of the Levenberg-Marquardt method as an inverse method for the estimation of the heat flux. In this paper inverse estimation of heat flux for a two-dimensional heat conduction problem is carried out. As a direct method, in the first attempt the solution of two-dimensional inverse heat conduction problem is formulated by using Lattice Boltzmann Method as a forward model. Later the solution to the problem is also obtained by using Finite Difference Method (FDM) as the forward model for the purpose of validation. Once the forward model is established, Levenberg-Marquardt Method is used as an inverse model to estimate the input parameter i.e. heat flux which is reported. A complete error analysis of inverse model with known values is performed. As the Lattice Boltzmann Method (LBM) is acclimatizing to parallel computation, its use is recommended in Levenberg-Marquardt method for the solution of inverse heat conduction problem which is evident from the results. © 2019 Elsevier Ltd.Item A Review on the development of lattice Boltzmann computation of macro fluid flows and heat transfer(Elsevier B.V., 2015) Arumuga Perumal, D.A.; Dass, A.K.The Lattice Boltzmann Method (LBM) is introduced in the Computational Fluid Dynamics (CFD) field as a tool for research and development, but its ultimate importance lies in various industrial and academic applications. Owing to its excellent numerical stability and constitutive versatility it plays an essential role as a simulation tool for understanding micro and macro fluid flows. The LBM received a tremendous impetus with their spectacular use in incompressible and compressible fluid flow and heat transfer problems. The applications of LBM to incompressible flows with simple and complex geometries are much less spectacular. From a computational point of view, the present LBM is hyperbolic and can be solved locally, explicitly, and efficiently on parallel computers. The present paper reviews the philosophy and the formal concepts behind the lattice Boltzmann approach and gives progress in the area of incompressible fluid flows, compressible fluid flows and free surface flows. © 2015 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V.Item Simulation of laminar flow in a three-dimensional lid-driven cavity by lattice Boltzmann method(2009) De, S.; Nagendra, K.; Lakshmisha, K.N.Purpose: The purpose of this paper is to apply lattice Boltzmann equation method (LBM) with multiple relaxation time (MRT) model, to investigate lid-driven flow in a three-dimensional (3D), rectangular cavity, and compare the results with flow in an equivalent two-dimensional (2D) cavity. Design/methodology/approach: The second-order MRT model is implemented in a 3D LBM code. The flow structure in cavities of different aspect ratios (0.25-4) and Reynolds numbers (0.01- 1000) is investigated. The LBM simulation results are compared with those from numerical solution of Navier-Stokes (NS) equations and with available experimental data. Findings: The 3D simulations demonstrate that 2D models may predict the flow structure reasonably well at low Reynolds numbers, but significant differences with experimental data appear at high Reynolds numbers. Such discrepancy between 2D and 3D results are attributed to the effect of boundary layers near the side-walls in transverse direction (in 3D), due to which the vorticity in the core-region is weakened in general. Secondly, owing to the vortex stretching effect present in 3D flow, the vorticity in the transverse plane intensifies whereas that in the lateral plane decays, with increase in Reynolds number. However, on the symmetry-plane, the flow structure variation with respect to cavity aspect ratio is found to be qualitatively consistent with results of 2D simulations. Secondary flow vortices whose axis is in the direction of the lid-motion are observed; these are weak at low Reynolds numbers, but become quite strong at high Reynolds numbers. Originality/value: The findings will be useful in the study of variety of enclosed fluid flows.© Emerald Group Publishing Limited.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 Study of adiabatic obstacles on natural convection in a square cavity using lattice boltzmann method(American Society of Mechanical Engineers (ASME) infocentral@asme.org, 2019) Karki, P.; Yadav, A.K.; Arumuga Perumal, D.A.This study involves the effect of adiabatic obstacles on twodimensional natural convection in a square enclosure using lattice Boltzmann method (LBM). The enclosure embodies squareshaped adiabatic obstacles with one, two, and four in number. The single obstacle in cavity is centrally placed, whereas for other two configurations, a different arrangement has been made such that the core fluid zone is not hampered. The four boundaries of the cavity considered here consist of two adiabatic horizontal walls and two differentially heated vertical walls. The current study covers the range of Rayleigh number (10 3 ? Ra ? 10 6 ) and a fixed Prandtl number of 0.71 for all cases. The effect of size of obstacle is studied in detail for single obstacle. It is found that the average heat transfer along the hot wall increases with the increase in size of obstacle until it reaches an optimum value and then with further increase in size, the heat transfer rate deteriorates. Study is carried out to delineate the comparison between the presences of obstacle in and out of the conduction dominant zone in the cavity. The number of obstacles (two and four) outside of this core zone shows that heat transfer decreases despite the obstacle being adiabatic in nature. © 2019 by ASME.Item A review of lattice boltzmann method computational domains for micro-and nanoregime applications(Begell House Inc., 2020) Narendran, G.; Arumuga Perumal, A.P.; Gnanasekaran, N.In the last two decades, microscale and nanoscale devices have received much interest due to the inevitable performance and their numerous applications not only in the field of fluid flow and heat transfer but also in bio-technology, bio-medical engineering, etc. In many situations, besides the conventional experiments and theoretical analysis, computations have emerged as a valuable tool for investigating the fluid transport and heat transfer phenomena. The lattice Boltzmann method (LBM) has emerged as an important option for micro-and nanoscale devices due to the fact that the LBM is well established for the range of Knudsen number. A comparative study on several working fluids used in the field of micro-and nanodevices such as microchannel, micro-cavity, microboiling, and nanochannel is categorized. Various aspects of nanofluids used in natural convection with different cavity configurations, flow boiling, immiscible fluids, liquid–vapor phase change are also critically reviewed. Different remarks and findings of available numerical results with several investigated parameters were summarized. © 2020 Begell House, Inc.Item 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 Authors