(SoE) School of Engineering

<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

The suspension strut cap is the major component of automobile, which attaches the suspension strut to the vehicle body. In addition, it insulates the tire noise & vibrations from the vehicle for generated due to rough road profile and speed breakers. The suspension cap is mounted at the top of suspension strut, where one side bolts to the vehicle (i.e. cap is directly attached to the body) and the other side to attached to the steering pivots of wheel. So as the vehicle moves and goes over bumps, the up & down impact pushes and pulls at the mount. The caused vibration can be transmitted into the vehicle if routine inspection has not been done and can cause wear and tear in bearing part of the mount (loosening of bolts). The damaged suspension cap can lead to clunking noises, noisy steering, excessive movement, tire alignment etc. Hence, conditional health monitoring of a suspension strut cap is vital in vehicles. For this study, the utilizations of dual sensing mechanism of piezo sensor has made for Structural health monitoring (SHM) technique i.e. Electro-Mechanical Impedance Technique. Different state of damage has been induced by loosening the bolts to different torque range and compared with pristine stage (when bolts are tightened to highest force). The admittance signature are plotted to verify the damage condition raised due self-loosening. The RMSD plots were drawn to quantify the level of damage. Finally the FE coupled simulation has done for the suspension strut mound with surface bonded PZT patch for different damage levels and results are compared with experimental results. The promising results for this study sets a new paradigm for SHM technologies. © 2019 9th ECCOMAS Thematic Conference on Smart Structures and Materials, SMART 2019. All rights reserved.

Civil Engineering

9th ECCOMAS Thematic Conference on Smart Structures and Materials, SMART 2019

Condition health monitoring of a suspension strut cap/ upper strut mount using piezoelectric sensor for electro-mechanical impedance technique

Facial expression recognition in videos is an active area of research in computer vision. However, fake facial expressions are difficult to be recognized even by humans. On the other hand, facial micro-expressions generally represent the actual emotion of a person, as it is a spontaneous reaction expressed through human face. Despite of a few attempts made for recognizing micro-expressions, still the problem is far from being a solved problem, which is depicted by the poor rate of accuracy shown by the state-of-the-art methods. A few CNN based approaches are found in the literature to recognize micro-facial expressions from still images. Whereas, a spontaneous microexpression video contains multiple frames that have to be processed together to encode both spatial and temporal information. This paper proposes two 3D-CNN methods: MicroExpSTCNN and MicroExpFuseNet, for spontaneous facial micro-expression recognition by exploiting the spatiotemporal information in CNN framework. The MicroExpSTCNN considers the full spatial information, whereas the MicroExpFuseNet is based on the 3D-CNN feature fusion of the eyes and mouth regions. The experiments are performed over CAS(ME)2 and SMIC microb expression databases. The proposed MicroExpSTCNN model outperforms the state-of-the-art methods. © 2019 IEEE.

World University root node

Computer Science and Engineering

Proceedings of the International Joint Conference on Neural Networks

Spontaneous Facial Micro-Expression Recognition using 3D Spatiotemporal Convolutional Neural Networks

The hashtag recommendation systems on Twitter have largely focused on analyzing the text content of tweets. In this work, we modify the state-of-the-art existing natural language processing (NLP) technique and deeply ingrain socio-temporal techniques into the overall process, to model a novel hashtag recommendation system. The social aspect of the system aims to make use of the hashtags generated by familiar individuals possess, as well as, the hashtags used by the individual at the past (profile). The temporal aspect aims to age the tweets, thereby ensuring that the more recent hashtags receive higher weights in the process of recommendation. The NLP technique is modified to offer an initial score based upon text embedding of hashtags, and a socio-temporal function and a burst function are applied to generate a final relevance score for hashtags towards a given tweet. The hashtags with top-K relevance scores are recommended to the user. © Springer Nature Switzerland AG 2019.

Studies in Computational Intelligence

A socio-temporal hashtag recommendation system for twitter

The flow over a stepped spillway has complex nature, and its characteristics are remarkably different from other kinds of spillways. This study conducts experimental investigations and numerical simulations on the flow behavior (velocity, concentration profile) and macroscopic features (interface position and self-aeration) of water and neutrally buoyant suspension of non-colloidal particles in a stepped spillway with uniform steps. The development of nappe, transition, and skimming flow regimes is experimentally investigated by using a flow visualization technique. The inception point related to air entrainments is identified in the experimental study. The inception point usually moves downstream and increases the length of the non-aerated region with the increase of flow rate. Results of numerical and experimental studies indicate that a vortex is formed in the triangular cavity below the pseudo-bottom line (imaginary line joining two adjacent step edges) in the stepped channel. This vortex rotates in a clockwise direction for a short time period and returns to the main flow to move downward in the channel. The velocity vector map from numerical simulation predicts the maximum velocity in the middle portion of the spillway, that is, near the pseudo-bottom line. A volume of fluid model coupled with a standard k-ε turbulence model is used in the CFD simulations to predict the location of the air-water air-suspension interface. The results are compared with experimental measurements. The calculated interface position agrees well with the experimental measurements. The migration and transport of particles are evaluated based on a diffusive flux model of shear induced particle migration. The contour map for velocity and particle concentration shows a remarkable increase in particle concentration near the air-suspension interface. © 2019, KSME & Springer.

Chemical Engineering

Journal of Mechanical Science and Technology

Experimental and computational study on flow over stepped spillway

Nonrenewable fossil fuels are finite resources that will ultimately deplete in near future. Nature sheds colossal amount of renewable wind energy but humans harvest a morsel. Taking this into account a numerical study is proposed on wind energy harvesting from a speeding subway train. Subways trains generate a remarkable gust of wind that can be transferred to useful electrical energy on daily basis. To this aim, a numerical analysis is modeled by placing Savonius wind turbine in a subway tunnel to crop the wind energy produced from the speeding train. The passage of train in the tunnel generates very high velocity slipstreams along the length of the tunnel. The slipstream phenomena develop a boundary layer regime that will be absorbed by the Savonius wind turbine to self-start and generate power. In the present study, a two-dimensional numerical simulation with modified turbine blade design is carried out using open source tool OpenFOAM® with PimpleDyMFoam solver coupled with six degrees of freedom mesh motion solver sixDoFRigidBodyMotion and k–ɛ turbulence modeling, to measure the amount of torque predicted by the rotor from the gust of wind produced by the speeding train in the tunnel. Being a self-start turbine with no yaw mechanism required the turbine collects air from any direction and converts it into useful power. © IMechE 2018.

Mechanical Engineering

Fulltext

Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science

Improved design of Savonius rotor for green energy production from moving Singapore metropolitan rapid transit train inside tunnel

In the current work we developed Ni-SiC based composite claddings on SS316L through microwave irradiation using different reinforcement weight fractions and particle sizes (micron to nano scale). A bimodal derivative using equal proportions of both micro and nano scale particles was also developed. Microstructural characterization showed claddings were composed of columnar structure with precipitated intermetallic phases segregated at the grain boundaries. The Ni-SiC bimodal particle reinforced claddings showed highest hardness and fracture toughness. All the developed claddings showed significantly high cavitation erosion resistance compared to SS316L steel. The Ni-10 wt\% SiC bimodal particle reinforcement cladding showed highest erosion resistance with around 5 times lower erosion rates than SS316L steel along with highest incubation period. The investigated bimodal particle reinforced cladding also outperformed the thermal sprayed WC10Co4Cr and Stellite 6 coatings and CA6NM hydroturbine steel used for comparison. Detailed structure-property correlation analysis showed that the exquisite performance of the investigated bimodal particle reinforcement cladding can be ascertained to high hardness and H/E ratio (inversely related with plasticity index). Compared to brittle failure mode exhibited by thermal spray coatings due to splat delamination, the Ni-SiC claddings showed mixed signatures of both ductile and brittle failure modes. Examination of the eroded surfaces of the claddings showed presence of significant number of micro pits surrounded by extruded lips and dislodged intracellular phase. Detailed SEM analysis of the samples near incubation period showed damage accumulation initiated around these intermetallic phases in the form of cracks and pits. It was shown that Ni-SiC based microwave-derived bimodal particle reinforced claddings are an effective and efficient solution for countering the cavitation induced erosion in fluid machinery. © 2019 Elsevier B.V.

Wear

Microwave synthesized composite claddings with enhanced cavitation erosion resistance

This work evaluates the performance of renewable and conventional energy power corporations of India using DEA. The analysis has been carried out based on both self and peer evaluation DEA models. Self-evaluation model reveals that only 7 out of 17 DMUs are CCR efficient. It has also been observed that amongst these fully efficient DMUs, 60\% are government funded electric utilities. Performance of several private corporations is sub-optimal, suggesting the potential for operation and maintenance cost reductions. In order to study the performance of renewable energy power plants, appropriate parameters have been chosen from the data set and results reveal that 75\% of the renewable energy generation plants have efficiency score greater than 0.75. Peer evaluation of the DMUs provides the basis for ranking based on the cross efficiency score. Aggressive and Benevolent models are used to study the performance of the DMUs under non-cooperative and cooperative conditions. Then the electric utilities that generate renewable energy are found to either maintain or improve their ranking under aggressive conditions. © 2018 IEEE.

Electrical Engineering

2nd International Conference on Energy, Power and Environment: Towards Smart Technology, ICEPE 2018

Comprehensive Evaluation of Renewable and Conventional Electric Utility of India under Noncooperative and Cooperative Environment

Primary breakup of a liquid jet emanating from a simplex swirl atomizer is numerically studied in this work. The liquid-gas interface is tracked using a coupled Level-Set VOF method. In order to improve the curvature calculation, a dual grid approach is used. Level set function is solved on a grid that is finer than the grid used to solve the rest of the variables. This solver is developed using OpenFOAM libraries and is validated by estimating the pressure profile and spurious velocities across the interface of a static bubble. The validation test shows significant improvement in the performance of curvature estimation without significant increase in the computational cost. Additionally, it is found that curvature calculation improves with increase in grid refinement index. A parametric study to understand the effects of grid refinement index on the flow features of the simplex swirl atomizer primary jet is reported here. Copyright © 2019 ASME

ASME 2019 Gas Turbine India Conference, GTINDIA 2019

Numerical study of primary jet breakup in a simplex swirl atomizer using dual grid coupled level set Vof method

Distributed generation (DG) integration benefits are manifold. When integrating into existing infrastructure, it reduces line losses when properly placed with the objective of loss minimization and at the same time it improves the system voltage profile. Besides these technical benefits there are economic and environmental benefits like upgrades deferment, reduction in operation and maintenance cost, reduction in greenhouse gases and a lot more. The paper proposes optimal DG placement for loss minimization in the distribution system. The DG considered here is solar photovoltaic system as type 1 distributed generator which supplies real power to the system. The analytical method is used for loss minimization problem using exact loss formula. The optimal DG capacity is determined for the objective of real power loss minimization as well as reactive power loss minimization. It is established and proposed that loss minimization with respect to DG placement is more if optimal DG sizes are determined with the objective of reactive power loss minimization. The economic benefits of the placement are determined and are distributed among the utility and the prosumer. © 2019, Institute of Advanced Scientific Research, Inc.. All rights reserved.

Journal of Advanced Research in Dynamical and Control Systems

Optimum solar photovoltaic generation placement in distribution system as real power generator for loss minimization using analytical method and its economic analysis

The focus of this work is on the development of asymptotically-accurate nonlinear hyperelastic constitutive model for thin shell structures using Variational Asymptotic Method (VAM). In this work, these structures are analyzed for both geometric and material nonlinearities. The geometric nonlinearity is handled by allowing finite deformations and generalized warping functions through Green strain, while the material nonlinearity is incorporated through strain energy density function of hyperelastic material model. Using the inherent small parameters (moderate strains, very small thickness-to-wavelength ratio and very small thickness-to-initial radius of curvature) for the application of VAM, the process begins with three-dimensional nonlinear hyperelasticity and it weakly decouples the analysis into a one-dimensional through-the-thickness nonlinear analysis and a two-dimensional nonlinear shell analysis. Through-the-thickness analysis is analytical work, providing 3-D warping functions and two-dimensional nonlinear constitutive relation for Nonlinear Finite Element Analysis of shells. Current theory and code are demonstrated through standard test cases and validated with literature. © Springer Nature Switzerland AG 2019.