Indian Institute of Technology Hyderabad (IITH) is a premier institute of science and technology established in 2008. IITH has been consistently ranked in the&nbsp;<a href="https://iith.ac.in/reports/" rel="noopener noreferrer">top 10 institutes</a>&nbsp;in India for Engineering&nbsp;<a href="https://www.nirfindia.org/2021/EngineeringRanking.html" rel="noopener noreferrer" target="_blank">according to NIRF</a>&nbsp;making it one of the most coveted schools for science and technology in the country.

IITH offers&nbsp;<a href="https://iith.ac.in/academics/under-graduate/">undergraduate programs</a>&nbsp;in all the classical engineering disciplines, applied sciences, design, as well as several modern interdisciplinary areas. Students are given a flexibility to explore a broad set of areas, and potentially pursue a minor or double major in a discipline that is not their own. Students who wish to seek a deeper understanding of their own discipline are strongly encouraged to get involved in cutting-edge research with the help of a faculty to mentor them, and earn an Honors in their own field.

The very foundation of IIT Hyderabad is based on&nbsp;<a href="https://iith.ac.in/research/">research and innovation</a>. The vibrant research culture is evident from the number of patents and publications that IITH produces consistently every year. IITH offers&nbsp;<a href="https://iith.ac.in/academics/programmes-offered/">graduate programs</a>&nbsp;at both a masters, and a doctoral level, in several diverse areas. There are separate programs for technology, design, science, and liberal arts. The&nbsp;<a href="https://iith.ac.in/academics/post-graduate/">MTech program</a>&nbsp;is offered in various modes and durations to cater to the ever-growing need of postgraduate level professionals in the country.

IITH encourages and supports&nbsp;<a href="https://iic-iith.netlify.app/index.html" rel="noopener noreferrer" target="_blank">innovation and entrepreneurship</a>&nbsp;at every stage. The minor program in entrepreneurship is open to all students of IITH, and many of the courses are offered by industrialists who are entrepreneurs themselves. There are various&nbsp;<a href="https://iith.ac.in/research/centres-incubators/">innovation centers and incubators</a>&nbsp;that promote entrepreneurship and help mentor young innovators. IITH has been very successful in building tie-ups with leading academic institutions around the globe.

IITH enjoys a very special relationship with Japanese universities and industries that goes beyond academic and research collaborations. In fact, some of the iconic buildings in IITH campus will carry the signature of Japanese architecture.

IITH creates a unique holistic ecosystem for education that offers interactive learning, a very flexible academic structure, cutting-edge research, strong industry collaboration, and entrepreneurship. This is an environment which enables students and faculty to translate their dreams into realities.

IIT Hyderabad

The equations of motion (continuity and momentum) describing the steady flow of incompressible power law liquids in a model porous medium consisting of an assemblage of long cylinders have been solved numerically using the finite difference method. The field equations as well as the pertinent boundary conditions have been re-cast in terms of the stream function and vorticity. The inter-cylinder interactions have been simulated using a simple "concentric cylinders" cell model. Extensive information on the detailed structure of the flow field in terms of the surface vorticity distribution, streamlines, and viscosity distribution on the surface of the solid cylinder as well as on the values of the pressure and friction drag coefficients under wide ranges of physical (0.4 ≤ ∈ ≤ 0.95; 1 ≥ n ≥ 0.4) and kinematic (0.01 ≤ Re ≤ 10) conditions have been obtained. The numerical results presented herein have been validated using the experimental results for the flow of Newtonian and power law fluids available in the literature; the match between the present predictions and the experiments was found to be satisfactory. © 2000 John Wiley & Sons, Inc.

World University root node

Department of Mechanical and Aerospace Engineering

Journal of Applied Polymer Science

Flow of Non-Newtonian Polymeric Solutions Through Fibrous Media

This work presents numerical simulations for the analysis of the impact of a bore against a wall. The 2D governing equations in the vertical plane are solved numerically using a variant of the simplified marker and cell method. Results are obtained for the maximum force and the runup height on the wall. Numerical results for the case of the vertical wall compare well with previous experimental data. A parametric study for the maximum force and the runup height on an inclined wall is presented. This work presents numerical simulations for the analysis of the impact of a bore against a wall. The 2D governing equations in the vertical plane are solved numerically using a variant of the simplified marker and cell method. Results are obtained for the maximum force and the runup height on the wall. Numerical results for the case of the vertical wall compare well with previous experimental data. A parametric study for the maximum force and the runup height on an inclined wall is presented.

Journal of Hydraulic Engineering

Numerical simulation of impact of bores against inclined walls

The complete Navier-Stokes equations describing the steady flow of incompressible Newtonian fluids normal to an array of long cylinders have been solved numerically using the finite difference method in terms of the stream function and vorticity variables. The inter-cylinder interactions have been mimicked using the well known free surface cell model. Extensive information on the detailed structure of the flow field in terms of the surface vorticity distribution, stagnation pressure, stream line and iso-vorticity line plots, as well as on the values of the integral quantities, such as pressure, friction and total drag coefficients, have been obtained under wide ranges of conditions as follows: 0.3≤ε≤0.99 and 0.01≤Re≤100. The numerical results presented herein have been validated using the appropriate theoretical and experimental results available in the literature; the match between the present predictions and the scant experimental results is good.

Canadian Journal of Chemical Engineering

Steady incompressible fluid flow over a bundle of cylinders at moderate Reynolds numbers

This work presents numerical computations for the analysis of Dam-Break Flow using two-dimensional flow equations in a vertical plane. The numerical model uses the general approach of the simplified marker and cell method combined with the volume of fluid approach for the surface tracking. The time evolution of flow depth at the dam site and the evolution of the pressure distribution are investigated for both wet and dry bed conditions. The effect of the initially nonhydrostatic state on the long term surface profile and wave velocity are studied. These long term effects are found to be marginal in the case of wet-bed conditions, but are significant in dry-bed conditions. The dry-bed tip velocity immediately after the dam break, computed numerically, compares well with analytical results published previously. The time taken to obtain a constant flow depth at the dam site increases with decreasing initial depth ratio. The numerical result for this time elapse for dry-bed conditions is close to the experimentally obtained value. This work presents numerical computations for the analysis of Dam-Break Flow using two-dimensional flow equations in a vertical plane. The numerical model uses the general approach of the simplified marker and cell method combined with the volume of fluid approach for the surface tracking. The time evolution of flow depth at the dam site and the evolution of the pressure distribution are investigated for both wet and dry bed conditions. The effect of the initially nonhydrostatic state on the long term surface profile and wave velocity are studied. These long term effects are found to be marginal in the case of wet-bed conditions, but are significant in dry-bed conditions. The dry-bed tip velocity immediately after the dam break, computed numerically, compares well with analytical results published previously. The time taken to obtain a constant flow depth at the dam site increases with decreasing initial depth ratio. The numerical result for this time elapse for dry-bed conditions is close to the experimentally obtained value.

Two-dimensional analysis of Dam-Break flow in vertical plane

The steady flow of power-law liquids normal to arrays of long circular cylinders has been studied theoretically. The governing equations (continuity and momentum) have been solved numerically using the finite difference method. The hydrodynamic interactions between cylinders have been accounted for by employing the so-called zero vorticity cell model which assumes each cylinder in the array to be surrounded by a hypothetical concentric envelope of fluid. Extensive results on the detailed kinematics of the flow in terms of the variation of the surface vorticity and the power-law viscosity on the cylinder surface, streamline and iso-vorticity plots as well as on gross fluid dynamic parameters in terms of the friction and pressure drag coefficients under wide ranges of conditions (0.01 ≤ Re ≤ 10; 1 ≥ n ≥ 0.5 and 0.95 ≥ ε ≥ 0.4) have been presented and discussed herein. The paper is concluded by performing comparisons between the present predictions and the scant analytical and experimental results available in the literature. The steady flow of power-law liquids normal to arrays of long circular cylinders has been studied theoretically. The governing equations (continuity and momentum) have been solved numerically using the finite difference method. The hydrodynamic interactions between cylinders have been accounted for by employing the so-called zero vorticity cell model which assumes each cylinder in the array to be surrounded by a hypothetical concentric envelope of fluid. Extensive results on the detailed kinematics of the flow in terms of the variation of the surface vorticity and the power-law viscosity on the cylinder surface, streamline and iso-vorticity plots as well as on gross fluid dynamic parameters in terms of the friction and pressure drag coefficients under wide ranges of conditions (0.01 ≤ Re ≤ 10; 1 ≥ n ≥ 0.5 and 0.95 ≥ ε ≥ 0.4) have been presented and discussed herein. The paper is concluded by performing comparisons between the present predictions and the scant analytical and experimental results available in the literature.

Journal of Non-Newtonian Fluid Mechanics

Power-law fluid flow across an array of infinite circular cylinders: A numerical study

An algorithm, based on the overlapping control volume (OCV) method, for the solution of the steady and unsteady two-dimensional incompressible Navier-Stokes equations in complex geometry is presented. The primitive variable formulation is solved on a non-staggered grid arrangement. The problem of pressure-velocity decoupling is circumvented by using momentum interpolation. The accuracy and effectiveness of the method is established by solving five steady state and one unsteady test problems. The numerical solutions obtained using the technique are in good agreement with the analytical and benchmark solutions available in the literature. On uniform grids, the method gives second-order accuracy for both diffusion- and convection-dominated flows. There is little loss of accuracy on grids that are moderately non-orthogonal. An algorithm, based on the overlapping control volume (OCV) method, for the solution of the steady and unsteady two-dimensional incompressible Navier-Stokes equations in complex geometry is presented. The primitive variable formulation is solved on a non-staggered grid arrangement. The problem of pressure-velocity decoupling is circumvented by using momentum interpolation. The accuracy and effectiveness of the method is established by solving five steady state and one unsteady test problems. The numerical solutions obtained using the technique are in good agreement with the analytical and benchmark solutions available in the literature. On uniform grids, the method gives second-order accuracy for both diffusion- and convection-dominated flows. There is little loss of accuracy on grids that are moderately non-orthogonal.

International Journal for Numerical Methods in Fluids

An overlapping control volume method for the Navier-Stokes equations on non-staggered grids

The effect of subtle changes in initial conditions on the evolution of global quantities in two-dimensional magnetohydrodynamic (MHD) turbulence is studied. It is found that a change in the initial phases of complex Fourier modes of the Elsässer variables, while keeping the initial values of total energy, cross helicity, and Alfvén ratio unchanged, has a significant effect on the evolution of cross helicity. On the contrary, the total energy and Alfvén ratio are insensitive to the initial phases. The simulations are based on direct numerical simulation using the pseudospectral method. © 1998 American Institute of Physics.

Fulltext

Physics of Plasmas

Initial condition sensitivity of global quantities in magnetohydrodynamic turbulence

Flow through the spiral casing of a hydraulic turbine was analysed. Reynolds averaged Navier-Stokes equations were solved using a finite element method. The physical domain was divided into a number of hexahedral elements which are isoparametrically mapped onto standard cubic elements. Numerical integration for the unsteady momentum equation is performed over such hexahedral elements to obtain a provisional velocity field. Compliance with the mass conservation equation and determination of the pressure correction are accomplished through an iterative procedure. The velocity distribution inside the spiral casing corroborates the results available in literature. The static pressure at the midplane generally decrases from the outside wall towards the exit of the spiral casing. Flow through the spiral casing of a hydraulic turbine was analyzed. Reynolds averaged Navier-Stokes equations were solved using a finite element method. The physical domain was divided into a number of hexahedral elements which are isoparametrically mapped onto standard cubic elements. Numerical integration for the unsteady momentum equation is performed over such hexahedral elements to obtain a provisional velocity field. Compliance with the mass conservation equation and determination of the pressure correction are accomplished through an iterative procedure. The velocity distribution inside the spiral casing corroborates the results available in literature. The static pressure at the midplane generally decreases from the outside wall towards the exit of the spiral casing.

A numerical study on flow through the spiral casing of a hydraulic turbine

Double-diffusive natural connective flow within a rectangular enclosure has been studied for an anisotropic porous medium using a non-Darcy extension. The principal direction of the permeability tensor has been taken oblique to the gravity vector. The spectral element method has been used to solve the problem numerically. The method has been validated using existing analytical and numerical results. Parametric studies are presented for isotropic and anisotropic cases for different fundamental parameters, e.g., buoyancy ratio, Lewis number, Rayleigh number, Darcy number. The results show that anisotropy causes significant changes in the Nusselt and Sherwood numbers. In particular, the present analysis shows that permeability orientation angle has a significant effect on the flow rate and, consequently, on the heat and mass transfer. © 1998, Taylor & Francis Group, LLC. All rights reserved.

Numerical Heat Transfer; Part A: Applications

Numerical study of heat and mass transfer in an anisotropic porous enclosure due to constant heating and cooling

This paper introduces a flux-limited scheme FLOCV for the overlapping control volume (OCV) approach to 2D steady and unsteady convection-diffusion problems on structured non-orthogonal grids. FLOCV switches from second- to first-order interpolation in the presence of extrema. Smooth switching between the two is ensured by weighted average second- and first-order upwind differencing, with the weights being dynamically determined. Five convective test problems are solved using this scheme and results are compared with known analytical solutions. It is found that FLOCV approximately retains second-order accuracy of the base discretization scheme on uniform grids and smooth non-uniform orthogonal and non-orthogonal grids, with little degradation of accuracy. This paper introduces a flux-limited scheme FLOCV for the overlapping control volume (OCV) approach to 2D steady and unsteady convection-diffusion problems on structured non-orthogonal grids. FLOCV switches from second- to first-order interpolation in the presence of extrema. Smooth switching between the two is ensured by weighted average second- and first-order upwind differencing, with the weights being dynamically determined. Five convective test problems are solved using this scheme and results are compared with known analytical solutions. It is found that FLOCV approximately retains second-order accuracy of the base discretization scheme on uniform grids and smooth non-uniform orthogonal grids. It is also found effective in removing oscillations for problems with discontinuities on both orthogonal and non-orthogonal grids, with little degradation of accuracy.

A bounded convection scheme for the overlapping control volume approach

This paper introduces a flux-limited scheme FLOCV for the overlapping control volume (OCV) approach to 2D steady and unsteady convection-diffusion problems on structured non-orthogonal grids. FLOCV switches from second- to first-order interpolation in the presence of extrema. Smooth switching between the two is ensured by weighted average second- and first-order upwind differencing, with the weights being dynamically determined. Five convective test problems are solved using this scheme and results are compared with known analytical solutions. It is found that FLOCV approximately retains second-order accuracy of the base discretization scheme on uniform grids and smooth non-uniform orthogonal grids. It is also found effective in removing oscillations for problems with discontinuities on both orthogonal and non-orthogonal grids, with little degradation of accuracy. © 1977 John Wiley & Sons, Ltd.

This investigation presents a fully spectral method for solving coupled hyperbolic partial differential equations. The spectral method is based on the Galerkin-collocation technique. Two different preconditioners the Preissmann and upwind schemes are evaluated for their performance in solving the discretized equations. It has been found, for the cases considered, that the upwind scheme is a viable preconditioner for the fully spectral discretization of hyperbolic PDEs. Its performance as a preconditioner is in every way superior to that of the Preissmann scheme. It is established that the relative accuracy of different numerical solutions is reliably indicated by the root-mean-square average of their residuals obtained by the discretization. It ts also established that the scheme gives much better accuracy than the finite-difference Preissmann scheme, for the same amount of computational effort, for both linear and non-linear problems.

International Journal for Numerical Methods in Engineering

A fully spectral method for hyperbolic equations

This paper introduces a finite volume method to solve 2D steady state convection-diffusion problems on structured non-orthogonal grids. Overlapping control volumes (OCV) are used to discretize the physical domain and the governing equations are solved without transformation. An isoparametric formulation is used to compute diffusion and for upwinding. Four test problems are solved using this and other schemes. The modelling of diffusion in OCV seems very effective even on distorted meshes. The convection modelling in OCV is found to be second-order-accurate, like QUICK, on regular meshes. Although its accuracy is slightly inferior to the latter on rectangular grids, its faster convergence gives it a better overall performance. On non-orthogonal grids, OCV gives better accuracy for a large and practical range of Peclet numbers than does QUICK applied to the transformed equations using the conventional five-point diffusion modelling. The results obtained also demonstrate that the scheme reduces false diffusion to a considerable extent in comparison with the power-law scheme.

Overlapping control volume approach for convection-diffusion problems

A comparison is made between the performance of the (aliased) Chebȳshev collocation method (CM) and the more recent Galerkin collocation method (GCM), which is a least‐squares collocation method, in solving the laminar, incompressible, steady boundary‐layer equations, which are parabolic in nature. An iterative procedure based on the preconditioned residual minimization method has been used. It is shown that the GCM is superior to the CM on several counts. Unlike the CM, the GCM minimizes the residual uniformly over the entire domain. The global accuracy of the solution is found to be higher in the GCM, at lower grid resolutions. The method also achieves much higher convergence rates. Unlike in the collocation method, the final residual values obtained in the GCM are good indicators of the level of accuracy achieved in the solution. It is highly likely that these results will be repeatable in other systems of parabolic partial differential equations. Copyright © 1995 John Wiley & Sons, Ltd

Communications in Numerical Methods in Engineering

A fully spectral solution method for parabolic equations

This investigation presents a spectral method for solving the one-dimensional shallow-water wave equations. The spectral method is based on the Chebyshev collocation technique and finite-difference time stepping. The spectral method and finite-difference Preissmann scheme are applied to route a log-Pearson Type III hydrograph through a wide rectangular channel, and the results are compared. The spectral method performs better than the Preissmann scheme as long as the time-stepping errors are kept low. However, for larger time steps, the Preissmann scheme, which is almost second-order accurate in time (and second-order accurate in space) performs better than the spectral scheme, which is first-order accurate in time and has so-called infinite-order accuracy in space. This seems to indicate that the order of accuracy in time discretization is more important than that in space discretization, in numerical models, for fast-rising floods and friction-dominated flows. © ASCE.