Mechanical 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 increased emphasis on vehicle and occupant safety in automotive accidents has necessitated research on vehicle crashworthiness during the design phase. The design of the bumper plays a significant role in mitigating pedestrian injuries and the risk of life during accidents. The present study is focused on the design and development of an economical external multilayered bumper that can be retrofitted to any car’s existing bumper fascia while improving the safety of pedestrians without compromising the safety of engine components. The proposed multilayered bumper consists of spring and damper assembly along with a layer of high-density polyurethane foam. Finite element analysis has been performed to compute the total deformation, equivalent Von-Misses stress, spring–damping coefficients, and energy absorption using the proposed bumper. An empirical relation amongst considered design parameters is formulated, which can be used to further develop the proposed modified bumper in any feasible ways. A comparative study has also been carried out between the crashworthiness of the conventional bumper and the developed bumper at various speeds. It is observed that a significant reduction of approximately 40% in the impact is observed with the proposed bumper compared to the conventional bumper. © 2021 Informa UK Limited, trading as Taylor & Francis Group.

World University root node

(SoE) School of Engineering

International Journal of Crashworthiness

Revamping the vehicle protection system using next-generation car bumper to mitigate pedestrian fatality

A hybrid computational fluid dynamics-artificial neural network approach is implemented to predict the thermo-hydraulic performance factor of a solar air heater with rotating circular ribs. Effects of rib height, rib pitch, and rib rotating speed are investigated for Reynolds numbers ranging from 3800 to 18000. A total of 432 different cases are simulated using CFD. Based on these data sets, an optimized ANN model is developed to predict thermo-hydraulic performance. The optimized ANN model has an architecture of 4-17-17-1 and it has a mean squared error of 3.89 × 10−6 for the testing data sets. The maximum thermo-hydraulic performance achieved is 1.57 for rib height of 1.4 mm, rib pitch of 25 mm, rib rotating speed of 10000 rpm at Reynolds number = 3800. The generalization capacity of the optimized ANN model is tested using experimental results and it is found that ANN predictions are in agreement with CFD simulation results. A comparison of computational time is also performed and approximately 100% reduction in computational time is achieved using the optimized artificial neural network model. This research establishes that ANN can be an excellent design tool for assessing the performance of novel solar air heaters. © 2022 The Author(s)

Energy Reports

Solar air heater with rotating circular ribs: Hybrid CFD-ANN approach for prediction of thermo-hydraulic performance

This article is intended to study the bending and vibration response of the exponentially graded FGM plate using the closed-form solution. The governing equations of motions are formulated on the basis of Hamilton's principle, whereas the Navier method has been used to solve the governing equation with simply supported boundary conditions. The results have been validated for non-dimensional deflection values of a square plate subjected to transverse loading. Apart from these, the exponential gradation model has been considered for calculating the effective material properties of a functionally graded plate and its mechanical properties are assumed to vary in the thickness direction. Bending analysis and non-dimensional frequency has been evaluated for various modes of vibration of functionally graded thin and thick plates. © 2022, Springer Nature Singapore Pte Ltd.

Lecture Notes in Mechanical Engineering

Bending and Free Vibration Analysis of Exponential Graded FG Plate Using Closed-Form Solution

A hybrid computational fluid dynamics-artificial neural network approach is applied to predict the thermo-hydraulic performance factor (THPF) of a solar air heater with vertical cylindrical ribs. 3-D CFD analysis considering effects of rib height, rib diameter, rib pitches are simulated for Re ranging 5000–24000. A total of 504 data sets for different cases are generated using CFD. Based on these data sets, an optimized ANN model is developed to predict the thermo-hydraulic performance. The optimized ANN model has an architecture of 5-25-1 and the mean squared error for this ANN model is 0.000051 for the testing data sets. The maximum THPF value achieved is 1.43 for rib height of 3.5 mm, rib diameter of 3 mm, rib transverse pitch of 20 mm and relative roughness pitch of 10 at Re = 8000. Global sensitivity analysis is also performed based on SHAP (SHapley Additive exPlanations) for the ANN model—Reynolds number is observed to be the most influencing factor with mean absolute SHAP value of 0.031 in predicting THPF along with transverse pitch which has SHAP value very close to Re. Computational CPU time comparison is also performed and approximately 100% reduction is achieved using the optimized ANN model. This research proposed a novel approach that could be successfully implemented in assessing thermal performance of solar-thermal collector systems. © 2022 The Author(s)

ANN model for prediction of thermo-hydraulic performance of a solar air heater with vertical cylindrical ribs

The present article investigates the effect of cutouts, porosity inclusion, and hygro-thermal environment on the vibrational characteristics of sandwich functionally graded material (FGM) plates resting on Pasternak elastic foundation. The governing equations for the sandwich FGM plates have been developed using the finite element method (FEM) with the conjunction of non-polynomial-based higher-order shear deformation theory (HSDT). The trigonometric shear-strain shape function has been used for the first time for sandwich FGM plates. The effective material properties with porosity inclusions have been computed using modified power–law distribution. The present results have been acquired by employing a C0 continuity isoparametric finite element (FE), using 4-noded elements with 7-DOF's per node. The accuracy of the current solution has been confirmed by convergence and validation studies. The influence of circular cutout, elastic foundations, hygro-thermal conditions, and geometric and boundary conditions on the vibrational frequency of porous sandwich FGM plates have been discussed in detail. © 2022 Taylor & Francis Group, LLC.

Mechanics Based Design of Structures and Machines

Influence of circular cutouts and elastic foundation on vibration characteristics of porous sandwich FGM plates under hygro-thermal environments

Assigning the right task to the right worker remains a challenge to an assembly line manager. This work is proposed to use digital-twin technologies for Assembly line worker assignment and balancing problems (ALWABP) for a collaborative assembly system. Applications of the Internet of Things, Data analytics and Learning algorithms are proposed to estimate the worker's work skill and task performance. Assembly line Digital Twin and collaborative robot (CoBot) work simulation tools are proposed to estimate the CoBot's assembly task performing ability and execution time. ALWABP framework is proposed to optimize the work allocation between the worker and the CoBot. Assembly line digital twin is furthermore proposed to simulate the ALWABP output during the decision-making process of the assembly line manager by considering the Human-in-the-loop decision-making system. Copyright © 2022 The Authors. This is an open access article under the CC BY-NC-ND license.

IFAC-PapersOnLine

A digital-twin based worker's work allocation framework for a collaborative assembly system

This paper presents an efficient and versatile OpenFOAM (Open-source Field Operation And Manipulation)-based numerical solver for fully resolved simulations that can handle any rigid and deforming bodies moving in the fluid. The algorithm used for solving Fluid–Structure Interactions (FSI) involving the immersed structure with changeable shapes is based on the momentum redistribution method. The present approach excludes the need to solve elastic equations, obtain high-accuracy predictions of the flow field and provide a rigorous basis for implementing the Immersed Boundary Method (IBM). The OpenFOAM implementation of the algorithm is discussed along with the design methodology for developing bio-inspired underwater vehicles using the present solver. The computational results are validated with the experimental observations of the two-dimensional and three-dimensional anguilliform swimmer case studies. The study further extended to the three-dimensional hydrodynamics of a bioinspired, self-propelling manta bot. The motion of the body is specified a priori according to the reported experimental observations. The results quantify the vortex formation and shedding processes and enable the identification of the portions of the body responsible for the majority of thrust. The body accelerates from rest to an asymptotic mean forward velocity of 0.2 ms−1 in almost 5 s, consistent with experimental observations. It is observed that the developed computational model is capable of performing any motion simulation and manoeuvrability analysis, which are critical for the designers to develop novel unmanned underwater vehicles. © 2022, Jilin University.

Journal of Bionic Engineering

Novel Hydrodynamic Analysis Towards Capabilities Improvement of Bio-inspired Underwater Vehicles Using Momentum Redistribution Method

The food and medical sectors have to abide by the strict regulations of quality control and this requires strict monitoring of various types of chemicals and pathogens. These requirements have brought laurels to the field of biosensing to develop the most capable sensors to detect a target property instantly as well as precisely. Biosensors integrated with the nanotechnological approach make them simple and tiny in size, which also provides a point-of-care platform. The last two decades have been devoted to developing different biosensors using nanoscale materials due to their sensitive and unique properties. Search is on, for the combination of materials for biosensors, which can make them multipurpose, inexpensive, and eco-friendly. The molecules or analytes can be detected through different working principles of biosensors. Biosensing is a wide area and several biosensors exist each with its working principles and/or sometimes a combination of two–three principles making them a hybrid sensor. This book chapter is aimed to revisit these working principles considering the growing use of newer nanomaterials (nanoparticles, nanowire, and nanosheet) in use for the development of biosensors. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Materials Horizons: From Nature to Nanomaterials

Nanomaterials Based Biosensing: Methods and Principle of Detection

Droplet grouping is important in technical applications and in nature where more than one droplet is seen. Despite its relevance for such problems, the fundamentals of the grouping processes are not yet fully understood. Initial conditions that expedite or impede the formation of droplet groups have been studied, but a thorough investigation of the temporal and spatial evolution of the forces at play has not been conducted. In this work, the grouping process in monodisperse droplet streams is examined in detail by direct numerical simulation (DNS), for the first time, using the multiphase code Free Surface 3D. The code framework is based on the volume-of-fluid method and uses the piecewise linear interface calculation method to reconstruct the interface. A method is established to quantify the development and evolving differences of pressure and shear drag forces on each droplet in the stream using the available DNS data. The results show a linear increase in the difference between the forces, where the drag force on the leading droplet is always larger than that on the trailing droplet. A comprehensive parametric study reveals that, on the one hand, large initial inter-droplet separation and small group distances increase grouping time due to reduced difference in the drag coefficients. On the other hand, higher initial Reynolds numbers and larger irregularities in the geometrical arrangement promote droplet grouping. The flow field shows stable wake structures at initial Reynolds numbers of 300 and the onset of vortex shedding at Reynolds numbers of 500, affecting the next pair of droplets, even for larger separation distances. © 2022 Author(s).

Physics of Fluids

Investigation of droplet grouping in monodisperse streams by direct numerical simulations

In this investigation, numerical analysis of square butt, butt with V-groove and T-weld joint configurations have been performed to estimate transient temperature distributions and residual stresses. A computational welding simulation based on a prescribed temperature approach was used that works on thermal load input derived from temperature analysis. In the thermal analysis, welding heat source or torch temperature was considered as the prescribed value of temperature, which helps in simulating real welding conditions. The inclusion of filler metal in the numerical analysis replicates the real welding phenomenon, which provides temperature distribution along the true distance of the joints. The maximum temperature was observed at the weld pool area and decreased in parabolic shape toward the base metal. Residual stresses were measured along the selected path (in the mid of plates) that comprises node-to-node variation of stresses in both longitudinal and transverse directions. von Mises and Tresca stress criterion was adopted to show accumulated stresses in the weld joints. It was observed that stresses accumulated in the different configurations of weld joints were below the yield strength 210 MPa of SUS304 steel. Peak values of stresses were observed at weld beads and in the nearby regions. © 2022, The Indian Institute of Metals - IIM.