Indian Institute of Technology Palakkad&nbsp;(IIT Palakkad or IIT PKD) is a public autonomous&nbsp;engineering&nbsp;and&nbsp;research&nbsp;institute located in&nbsp;Palakkad,&nbsp;Kerala. It was&nbsp;one of the five new&nbsp;IITs&nbsp;proposed in the&nbsp;2014 Union budget of India. The campus was inaugurated on 3 August 2015. The institute has 94 faculty, 978 students, and 63 non-teaching staffs.

IT Palakkad currently offers four-year Bachelor of Technology (B.Tech) and two years MS programmes in 8 different engineering disciplines including&nbsp;Computer Science, Electrical, Mechanical, Civil among others.

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IIT Palakkad

Vapour bubble growth in film boiling occurs as a result of the increase in disturbances at the liquid vapour interface. Increase in heat flux stimulates these disturbances with the included effects of buoyancy and capillary forces acting at the interface. The present report is focussed on the analysis of the effect of electrohydrodynamics (EHD) on the heat transfer rate and bubble behaviour in saturated film boiling with different wall superheat. The analysis is done with the increasing electric field intensity to observe the space averaged Nusselt number variation and the growth rate of the interface. The destabilizing nature of the electric field force results in the faster rate of bubble release with decreasing distance between adjacent bubbles which verify the decrease in the critical wavelength of disturbance. Combined level-set and volume of fluid (CLSVOF) technique is utilized to capture the liquid-vapour interface. © 2021, Begell House Inc. All rights reserved.

World University root node

Department of Mechanical Engineering

International Symposium on Advances in Computational Heat Transfer

Effect of electrohydrodynamics in saturated film boiling with varying superheat

In this work, a simple and efficient numerical approach to determine the shape of the minimum-drag axisymmetric forebody in inviscid supersonic flow with an attached shock constraint has been described. Taylor–Maccoll equation in conjunction with the tangent cone method is employed to estimate the pressure drag coefficient which is also chosen as the cost function. The forebody geometry is parameterized using a Non-Uniform Rational B-Splines (NURBS) curve whose control points are the design variables for optimisation using the steepest descent algorithm. Numerical studies demonstrate that the optimal forebody geometry for a given length and base radius has as much as 15 % lesser drag, depending on the Mach number than a cone of the same fineness ratio and that the convergence to the optimal solution exhibits a relatively weak Mach-number dependence. © 2014, The Institution of Engineers (India).

Journal of The Institution of Engineers (India): Series C

Optimal Forebody Shape for Minimum Drag in Supersonic Flow

A novel heuristic approach to resource estimation and target determination in interrupted and shortened Twenty20 cricket matches is presented. The present approach mimics Kleiber's allometric relation to define the effective resources for a team. Unlike existing methods, the present methodology computes the resources using a simple non-statistical method to decide on the revised target, called the Kleiber target, in interrupted matches. The proposed approach is applied to a wide range of real-match scenarios involving one or more interruptions. Case studies show that the Kleiber target is consistent and reasonable over a spectrum of match situations and offers an inexpensive, robust and elegant methodology to reset targets in shortened Twenty20 matches. © 2015 Institution of Mechanical Engineers.

Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology

Bio-allometry inspired resource estimation in Twenty20 cricket

A generic methodology for the design of interface capturing schemes for immiscible multi-fluid flows using the VOF (Volume-Of-Fluid) approach is outlined. Interface capturing schemes are devised as a blend of high-resolution and compressive schemes and their efficiency and accuracy are dependent on the choice of the constituent schemes and the blending function. On the basis of a set of design principles proposed in this work, we show that interface capturing schemes proposed in literature may be encompassed into a single class of GPL (Generalised Piecewise Linear)-κ schemes allowing for a unified approach for development of such schemes. This methodology is used to de-construct four existing schemes and to propose two new schemes for interface capture in an unstructured finite volume framework. The schemes are tested on challenging advection problems using both structured and unstructured grids to evaluate their performance. The new schemes perform as well as existing schemes and even outperform them on unstructured grids, while also exhibiting near Courant number independence for all test problems and grid topologies. The CUIBS (Cubic Upwind Interpolation based Blending Scheme) proposed in the study shows the best performance among all interface capturing schemes discussed herein and is applied to the study of immiscible binary fluid flows. Numerical simulations of viscous sloshing in a tank and Rayleigh-Taylor instability demonstrate the ability of the CUIBS scheme to resolve fluid-fluid interfaces with minimal diffusion. © 2014 Elsevier Ltd.

Computers and Fluids

A generic framework for design of interface capturing schemes for multi-fluid flows

Numerical investigations to assess the performance of different flux schemes for the spatial discretisation of the Euler equations have been performed. The schemes employed in the study include flux vector and flux difference splitting schemes as well as hybrid schemes. The schemes are cast in an unstructured high-order finite volume framework and are studied on typical engineering problems in the supersonic and hypersonic regimes. While all the flux schemes perform well in the supersonic and low hypersonic range, their performance show a marked change in the high Mach number regimes. Numerical experiments suggest that the AUSM family of schemes is the most accurate while the Rusanov scheme is the most robust for the range of Mach numbers considered in the study. These studies indicate that a robust and accurate numerical solver for high-speed compressible flows necessitate the use of blended schemes that provide a right balance between accuracy and numerical dissipation. © 2014 Inderscience Enterprises Ltd.

Progress in Computational Fluid Dynamics

Performance comparison of flux schemes for numerical simulation of high-speed inviscid flows

The importance of fineness ratio in determining the aerodynamic shapes of minimum-drag, zero-lift axisymmetric bodies in inviscid hypersonic flows is investigated using a shape optimization framework. The framework employs modified Newtonian theory for surface pressure computation, Bezier curves for geometric parameterization and a steepest-descent approach for minimization of the wave-drag coefficient. Studies are performed on axisymmetric bodies of a given length for fineness ratios varying from 1 to 6 and Mach numbers ranging from 6 to 12. It is shown that the optimal axisymmetric body for a given freestream Mach number is blunt-nosed for smaller fineness ratios but becomes sharp-nosed at larger fineness ratios. The fineness ratio at which the optimal body of revolution transitions from blunt-nosed to sharp-nosed is found to be nearly constant at hypersonic speeds and is around 3. Results indicate that the optimal bodies derived from the framework are superior in terms of wave drag to the von Kármán ogive but comparable to the 0.7 power-law body. High-resolution Euler simulations of these optimal forebodies demonstrate that, while the modified Newtonian theory underpredicts the wave drag for lower values of the similarity parameter, the derived configurations remain "near-optimal" for the entire range of the similarity parameter in the hypersonic regime. The study hints at the possibility of multiple near-optimal configurations in inviscid hypersonic flows and affirms the utility of the present framework as a low-fidelity approach for the design of minimum-drag configurations. Copyright © 2013 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

Journal of Spacecraft and Rockets

Effect of fineness ratio on minimum-drag shapes in hypersonic flows

Shock-wave boundary layer interaction (SWBLI) and associated changes in wall properties for ramp induced flow breakdown have been considered in the present studies. A two dimensional finite volume based CFD solver has been developed and implemented successfully to study the SWBLI. Pressure measurements are invariantly considered in the literature for qualitative prediction of various SWBLI parameters. Hence efforts are made herewith to understand the laminar boundary layer separation in the presence of ramp induced shock wave through surface heat transfer rates, wall skin friction coefficient and wall pressure distributions. Effect of variation of freestream and wall properties along with geometric changes is considered in present studies. It has been observed from present limited investigations that ratio of wall temperature to freestream stagnation temperature is the governing parameter for SWBLI instead of the individual temperatures. Increase in Mach number is found to suppress the upstream influence which results in decrease in extent of separation. Efforts are also made to study the effect of leading edge bluntness on the SWBLI. These studies are found useful to confirm the earlier reported experimental observations regarding turbulent re-attachment. © 2013 Elsevier Ltd. All rights reserved.

International Journal of Heat and Mass Transfer

Shock wave boundary layer interactions in hypersonic flows

A new algorithm to recover centroidal velocities from face-normal data on two-dimensional unstructured staggered meshes is presented. The proposed approach uses iterative defect correction in conjunction with a lower-order accurate Gauss reconstruction to obtain second-order accurate centroidal velocities. We derive the conditions that guarantee the second-order accuracy of the velocity reconstruction and demonstrate its efficacy on arbitrary polygonal mesh topologies. The necessity of the proposed algorithm for non-Newtonian flow simulations is elucidated through numerical simulations of channel flow, driven cavity and backward facing step problems with power-law and Carreau fluids. Numerical investigations show that second-order accuracy of the reconstructed velocity field is critical to obtaining physically consistent solutions of vorticity-dominated flows on non-orthogonal meshes. It is demonstrated that the spurious solutions are not linked to discrete conservation and arise solely due to the lower order accuracy of velocity reconstruction. The importance of the proposed algorithm for hemodynamic simulations is highlighted through studies of laminar flow in an idealized stenosed artery using different blood models. © 2014 Elsevier Inc.

Journal of Computational Physics

Defect correction based velocity reconstruction for physically consistent simulations of non-Newtonian flows on unstructured grids

We propose a novel algorithm for velocity reconstruction from staggered data on arbitrary polygonal staggered meshes. The formulation of the new algorithm is based on a constant polynomial reconstruction approach in conjunction with an iterative defect correction method and is referred to as the IDeC(k) reconstruction. The algorithm is designed for second order accuracy of the reconstructed velocity field and also leads to a consistent estimate of velocity gradients. Accuracy, convergence and robustness of the new algorithm are studied on different mesh topologies and the need for higher-order reconstruction is demonstrated. Numerical experiments for several cases including incompressible viscous flows establish the IDeC(k) reconstruction as a generic, fast, robust and higher-order accurate algorithm on arbitrary polygonal meshes. © 2011 Elsevier Inc.