Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

In this research work, a computational modeling of multi-phase flow through an asymmetric exhaust hood is presented. The three-dimensional Navier–Stokes equations along with the standard (Formula presented.) turbulent model and the Eulerian–Eulerian multi-phase equations were solved. The coupling of the last stage turbine blades and the exhaust hood has been carried out using the actuator disc model, which is less computationally demanding. The finite volume-based commercial computational fluid dynamics solver, ANSYS FLUENT, is used for the present numerical simulations. The effects of wetness on the flow structure and the pressure recovery capacity of a steam turbine exhaust hood have been investigated. One of the salient findings is that the pressure recovery capacity of a steam turbine exhaust hood enhances due to wetness effects. Wetness-induced turbulence damping is noted to be playing a crucial role in the enhancement of pressure recovery capacity of an exhaust hood. © IMechE 2020.

Department of Thermal and Energy Engineering

School of Mechanical Engineering

Vellore Campus

World University root node

Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy

Computational investigation of multi-phase flow effects on the performance of the steam turbine exhaust hood

A fusion reactor must be fueled by solid pellet injection at the high field side to ensure uniform fuelling and meet the fuel cycle requirements. A reliable extrusion system must be developed to solidify and extrude the fuel in the form of a fine filament. Over the past few decades, various extrusion systems such as in-situ, piston-cylinder, single screw, twin screw extrusion were developed to progress into achieving the extrusion rate specified by ITER (International Thermonuclear Experimental Reactor). Among these techniques, twin screw extruder promises to be reliable due to its continuous operation and stable throughput. This review article has twin objectives. First, it seeks to provide an overview of developments carried out so far for the cryogenic extruders like conceptualization, prototype development and performance. The numerical modelling of cryogenic extruders is at infant stage. Therefore, the second objective of this paper is to review various numerical models from polymer extrusion research and explain the need to adopt those models to arrive at the more optimal design of an extruder. In addition, the thermo-physical properties of hydrogenic fuels are reviewed, which is very important for developing numerical models. Also, this paper brings out the critical gaps that exist in the CFD modelling of a twin screw extruder. The present review work would be of great importance to the scientific community working toward plasma fueling. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

Journal of Fusion Energy

Development of Cryogenic Extrusion Techniques and Modelling of a Twin Screw Extruder: A Review

A proper design of exhaust hood geometry is very much essential in order to improve the overall efficiency of the steam turbine plant. The geometry of the non-axisymmetric exhaust hood makes the fluid flow at the exit of the steam turbine to be radially and circumferentially non-uniform. This work involves computational simulation of steam turbine asymmetric exhaust hood flows by incorporating the actuator-disc concept. The ANSYS FLUENT, finite volume based CFD solver is used for the present computational study. In the present simulation, the implementation of actuator disc boundary conditions with and without tip leakage is described in detail. The Actuator disc model approach exhibits a similar steam turbine exhaust hood flow asymmetry and static pressure recovery compared with the results reported in the literature, highlighting the applicability of the present model in coupling the rotor tip leakage jet with the steam turbine hood flow structure with less computational effort. © Isfahan University of Technology.

Department of Automotive Engineering

Fulltext

Journal of Applied Fluid Mechanics

An alternative numerical model for investigating three-dimensional steam turbine exhaust hood

Aerodynamic aspects of train shapes suitable for Vacuum Tube Train System are investigated in this paper. Three feasible geometries for the vacuum tube train system have been considered and modelled in three dimensions and have been computationally studied using the commercial software Ansys Fluent. Aerodynamic drag loads on these geometries have been calculated under different tube pressures and speeds of the train, which provide insight on various operating parameters that need to be considered while designing the vacuum tube train system. The present computational research shows that, the suitable vacuum pressure, and different shapes of head and tail of the train have significantly effects the drag force of the vacuum train in the tunnel. Overall, the elliptical train shape with a height to base ratio of 2:1 is more efficient for aerodynamic drag reduction of the vacuum tube train at the vacuum tube pressure of 1013.25 Pa. © 2019 Isfahan University of Technology.

CFD analysis of aerodynamic drag effects on Vacuum Tube Trains

This paper documents all the important works in the field of conjugate heat transfer study. Theoretical and applied aspects of conjugate heat transfer analysis are reviewed and summarized to a great extent on the light of available literature in this field. Over the years, conjugate heat transfer analysis has been evolved as the most effective method of heat transfer study. In this approach the mutual effects of thermal conduction in the solid and convection in the fluid are considered in the analysis. Various analytical and computational studies are reported in this field. Comprehension of analytical as well as computational studies of this field will help the researchers and scientists who work in this area to progress in their research. That is the focus of this review. Early analytical studies related to conjugate heat transfer are reviewed and summarised in the first part of this paper. Background of theoretical studies is discussed briefly. More importance is given in summarising the computational studies in this field. Different coupling techniques proposed to date are presented in great detail. Important studies narrating the application of conjugate heat transfer analysis are also discussed under separate headings. Hence the present paper gives complete theoretical background of Conjugate heat transfer along with direction to its application envelope. © 2018, CIMNE, Barcelona, Spain.

Archives of Computational Methods in Engineering

Applied and Theoretical Aspects of Conjugate Heat Transfer Analysis: A Review

An analysis of the exhaust diffuser section of a gas turbine is presented by incorporating the reduced order mathematical model "actuator disc concept" that represents the last stage of the turbine. The actuator disc model is one of the simplified numerical methods for analyzing the aerodynamic performance of axial turbine stage. In which, the rotor and the stator of the turbine stages are modeled as zero thickness discs with a specified blade speed and zero speed respectively. Finite volume based commercial CFD package ANSYS FLUENT was employed for the numerical investigation of the applicability of the proposed simplified model. The compressible Navier-Stoke equations along with k-ε turbulent model were solved in the computational domain by incorporating suitable boundary conditions. The implementation of actuator disc boundary conditions is described in detail. The numerical results obtained from the proposed model are in good agreement with the experimental data available in the literature. The effect of casing angle on the performance of diffuser is presented. © 2019 Isfahan University of Technology.

Numerical simulation of diffuser of a gas turbine using the actuator disc model

Low HDL-cholesterol and high LDL-cholesterol in plasma have long been associated with cardiovascular disease (CVD) risk. The quantity of cholesterol associated with these lipoproteins is being traditionally used to predict CVD risk. However, recent studies have suggested that the quality and functionality of these lipoproteins are more important. The lipoproteins - HDL and LDL - undergo both enzymatic and non-enzymatic modifications which impair their functional capability and hence, test of such modification which reflects the quality of HDL can be a good predictor of CVD risk. The present article discusses oxidation- associated dysfunctionality of lipoproteins and their potential in laboratory diagnosis of CVD. © 2018 Current Science Association, Bengaluru.

Centre for Bio-Separation and Technology

Current Science

Oxidized Lipoproteins as the Diagnostic Target for Cardiovascular Diseases

The eco-friendly nature as well as processing advantage, light weight and low cost have enhanced the attraction and interest of natural fibre reinforced composite. The objective of current study is to study mechanical and interfacial properties of jute reinforced low density polyethylene composites and sisal fibre low density polyethylene composites and to compare the properties with jute-sisal reinforced hybrid composite. The composites are to be prepared by film stacking followed by hot compaction process. Tensile, flexural, impact and hardness tests are to be conducted for mechanical characterization. © 2006-2018 Asian Research Publishing Network (ARPN).

Department of Design and Automation

ARPN Journal of Engineering and Applied Sciences

Fabrication and mechanical analysis of jute-sisal hybrid composite

A Scramjet engine (Supersonic Combusting Ramjet) entails combustion at supersonic flow by generating high pressure through recompression (oblique) shock train. Shock Boundary Layer Interaction (SBLI) is an undesirable phenomenon that occurs inside the scramjet intake which has a detrimental effect on its performance. Due to adverse pressure gradient created by SBLI, the flow might be decelerated to subsonic speeds via normal shock. This leads to unstarting of the engine including other undesirable phenomena such as high drag and increased localized heating. The effect of cowl angle is studied on the performance of the scramjet engine in this study. A scramjet inlet prototype is designed in Solid Works followed by CFD analysis using ANSYS tool. The effects of cowl angle, static pressure rise, total pressure recovery and Flow Distortion are brought out. © IAEME Publication.