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

Mechanical

The present study focuses on the influence of tin coated hydroxyapatite (HA) particles reinforced in Mg-5 wt.% Sn matrix on corrosion resistance. Electroless coating process has been used to coat hydroxyapatite particles with tin. From the results, it was understood that the electroless coating is a potential technique to successfully coat Sn on HA particles which helps in refinement of grains and uniform distribution of phases. It also prevents the dissociation of HA, thereby formation of unwanted phases such as CaSn which could be detrimental for corrosion properties due to galvanic coupling. The biodegradation was reduced by the addition of Sn coated HA in comparison with reinforcement of uncoated HA particles. © 2020 Elsevier Ltd

School of Mechanical Engineering

Chennai Campus

World University root node

Composites Communications

Electroless tin coated hydroxyapatite reinforced Mg–Sn alloy composite for enhanced bio corrosion resistance and bioactivity

The ordinary vehicle suspension system scatters the mechanical vibration vitality as a considerable amount of waste heat. In recent times the regenerative suspension systems have pulled in much consideration for the augmentation of vibration attenuating performance as well as the reduction of energy dissipation or harvesting the same. The main objective is to fabricate a prototype of Suspension Energy Regeneration System (S.E.R.S.) at a convenient cost for the automobile industry, further conduct the experiments, and analyse the power output. Also, to raise the fuel efficiency of the engine by decreasing the consumption of electrical energy produced by the I.C. engine by harvesting the same energy from S.E.R.S. Thus, reducing the fuel energy wastage and promote sustainable development. The main focus is to evaluate the possibility of using dynamo as a damping module in the Suspension system. The performance analysis was done to observe the differences between the operations of the conventional suspension system and S.E.R.S. After carrying out the necessary study, the simplified design of S.E.R.S. was made and fabricated which was cost-efficient as well as had enough power regeneration to support auxiliary electronic system in vehicles like audio system, headlights, etc. © Published under licence by IOP Publishing Ltd.

Fulltext

IOP Conference Series: Earth and Environmental Science

A Design Analysis of Suspension Energy Regenerative System Using Dynamo Damping

The experimental analysis on the influence of duty factor and powder particle size on discharge energy, material removal rate and surface integrity is made during powder mixed electrical discharge machining process. Molybdenum-di-sulfide (MoS2) powder particles of two different size viz. 40μm (micro) and 90 nm (nano) are used. During experimentation duty factor is varied as 2, 4, 6, 8, 10 and 12. A comparative evaluation on the effect of using two size of molybdenum-di-sulfide powder particle in dielectric medium is studied. For all duty factors, micro powder offered high discharge energy and better surface finish compared to that of nano powder. Nano powder offered high material removal rate compared to that of micro powder. The occurrence of series discharge during powder mixed electrical discharge machining is observed using pulse train generated in gap and using scanning electron microscope image of machined surface. The e energy dispersive X-ray spectroscopy analysis of machined surface reveals the deposition of molybdenum-di-sulphide from dielectric medium for both micro and nano powder mixed electrical discharge machining process. © Published under licence by IOP Publishing Ltd.

IOP Conference Series: Materials Science and Engineering

Comparison on machining characteristics of AISI 304 steel during micro and nano powder mixed electrical discharge machining process

Natural fibers are known for their biodegradable and abundant availability, which makes them a potential replacement for synthetic fibers. An attempt is made in this work to study the thermal buckling behavior of a jute-fiber-reinforced epoxy polymer matrix composite plate. A numerical model is developed to study the thermal buckling behavior of the composite using the commercial finite-element analysis software Ansys. The result obtained from the numerical model is validated using experimental analysis and with the theoretical values published in the literature. The developed numerical model is suited very well for isotropic and composite materials. The influence of the number of plies, orientation and boundary conditions on the thermal buckling behavior of the composite is also studied using parametric analysis. The effects of boundary conditions such as 'clamped' and 'simply supported' on cross-ply symmetric, antisymmetric, balanced and quasi-isotropic laminates are investigated. © 2020 ICE Publishing: All rights reserved.

Department of Design and Automation

Vellore Campus

Emerging Materials Research

Investigation on thermal buckling analysis of jute/epoxy polymer matrix composites

This work analyzed the mechanical and vibration characteristic of the banana fiber sandwich layer with core AISI 304 steel wire mesh (WM). The following specimen configurations were prepared by hand lay-up method by varying fiber orientation in the skin layer: S = 0/0/0/0, S1 = 0/0/WM/0/0, S2 = 0/90/WM/90/0, S3 = 0/45/WM/-45/0 and S4 = 0/30/WM/60/0. The primary mechanical properties of the sandwich composite specimens were obtained by conducting Tensile, Flexural, and Impact strengths as per ASTM standards, whereas secondary vibration characteristics by experimental modal analysis. The presence of core WM enhances the primary properties especially in S1 attributed to the 0° fiber orientation with high load carrying capacity, natural frequency (Mode I, II), and stiffness. Whereas the specimen with angular fiber orientation (S2, S3, S4) in the skin layer exhibits higher damping showcasing their ability to dissipate energy. Specimen ‘S3ʹ acts as a performance change over with 45/-45 fiber in the skin layer. Morphology study of a test of a specimen with ‘WM’ shows the participation of matrix, banana fiber, and WM in load transfer mechanism with varied failure pattern. Hence, this type of composite structure can be preferred to use in structural and automobile applications by properly orienting the fiber in the skin layer. © 2020 Taylor & Francis.

Journal of Natural Fibers

Mechanical and Vibrational Property Evaluation of Banana Fiber Epoxy Sandwich Composite with Steel Wire Mesh Core

In this study, machining characteristics of polymer composite consisting of banana fiber and silicon carbide (SiC) as reinforcements and epoxy resin as matrix are investigated. Rein-forcement phases consist of raw banana fiber powder sieved to 100 microns size of 1% (w/w) and SiC powder of 1% (w/w). The conventional machining process is carried out on the fab-ricated composite samples by considering the depth of cut, feed rate and speed as influential parameters. The central composite design (CCD) is used to design the experiment based on response surface methodology (RSM). The analysis of variance (ANOVA) is used to study the influences of the depth of cut, feed rate and the speed on the material removal rate (MRR) and surface roughness. The results reveal that the feed rate is the most influential parameter for minimizing surface roughness and maximizing MRR. It is observed that the feed rate plays an important role in determining the surface roughness and MRR followed by the depth of cut and speed. The optimized parameters for maximum MRR and minimum surface roughness are also obtained. © 2020, Polska Akademia Nauk. All rights reserved.

Engineering Transactions

Investigation on machining characteristics of banana fiber and silicon carbide reinforced polymer matrix composites

Electricity has been paid much attention towards its entry in all sectors of human life, ever long since its revolutionary invention. Networking the disconnected hamlets with reliable electricity is still found to be challenging in many countries, due to demographic conditions, where electricity remains elusive. Solar energy, a form of renewable energy that has been proved to be a viable alternative to fossil fuels could bea potential solution for regions with poor distribution of power. The present work aims t augmenting the solar energy harvesting in a PV module with a phase change material. A portable PV module is fabricated based on an innovative design including passive cooling with paraffin wax and arrangements for enhanced solar irradiation. The new design is tested for its performance at different temperatures and it is found that the module with PCM has shown 3% of increase in voltage generation over the conventional one. Also, paraffin wax is found to maintain the module temperature at 5% lesser than the normal one on an average. Five different angles of orientation of the mirrors say, 30°, 45°, 60°, 75° &amp; 90° with module axis are tested and it is observed that 60° is optimum in harvesting the voltage. The results revealed that the new design is more efficient and viable for its usage. © Published under licence by IOP Publishing Ltd.

Effect of Phase Change Material and orientation angles on the efficiency of hexagonal solar Photo-voltaic module

Cooling tower is a type of heat exchanger used to dissipate the unwanted heat from a medium into the atmosphere. A well-designed cooling tower provides prolong contact time for water with air and breaks down the water to have large surface area to promote the heat transfer rate. In the present work, an induced draft cooling tower is fabricated and used with a stationary IC Engine to minimize the overall usage of water. The performance of the tower with two different bed materials (Jute carpet &amp; Polystyrene balls) with and without wire mesh at three different water flow rates viz., 12, 18 and 30 lpm are studied. The cooling tower parameters such as range, approach, efficiency, effectiveness, heat loss, windage losses, and evaporative losses are calculated from the experimental data. At higher flow rates, jute carpets with wire mesh provided optimal results for the parameters while at low flow rates polystyrene balls are found to provide better results. The experimental results showed that the efficiency of the cooling tower increased by 67% as the flow rate increased from 12 lpm to 30 lpm with jute carpet and wire mesh, whereas the efficiency decreases as the flow rate increases with polystyrene as the bed material. Also, the similar trend is observed for the effectiveness of cooling tower. © Published under licence by IOP Publishing Ltd.

An Efficient Cooling Tower for a Stationary Engine

The main objective of the proposed research study is to discriminate different blade fault conditions which affect the wind turbine blades under operating condition through machine learning approach. A three bladed wind turbine was chosen and the faults like blade bend, blade cracks, blade erosion, hub-blade loose connection and pitch angle twist were considered in the study. This problem is formulated as a machine learning problem which consists of three phases, namely feature extraction, feature selection and feature classification. Histogram features were extracted from vibration signals and feature selection was carried out using J48 decision tree algorithm. Feature classification was performed using lazy classifiers like nearest neighbour, k-nearest neighbours, locally weighted learning and K-star classifier. The results of these classifiers were compared with respect to their correctly classified instances (accuracy percentage) and found that, locally weighted learning yielded a maximum accuracy of 93.83% with a computational time of 0.07 s. © 2019 Elsevier Ltd

Measurement

A lazy learning approach for condition monitoring of wind turbine blade using vibration signals and histogram features

The aim of the study is to evaluate the tribological behavior of dental Zirconia as it undergoes surface and subsurface damages during CAD/CAM milling. These damages cannot be healed in the subsequent fabrication processes leading to shortened lifetime of dental restorations. Four groups based on pre- and post-processing combinations are selected for the study. The groups included milling of pre-sintered blocks followed by sintering and polishing (Group A), polishing of pre-sintered block followed by sintering (Group B), sintering followed by sandblasting with aluminum oxide (Al2O3) and polishing (Group C), and polishing of pre-sintered blocks followed by sintering and sandblasting with aluminum oxide (Al2O3) (Group D). Each of the specimens is tested for wear using an antagonist Zirconia ball of 6 mm diameter and abraded for 7200 cycles at 2 Hz with 15 mm stroke length on a reciprocating tribometer. A load of 10 N was applied and the test is performed in the presence of artificial saliva. The surfaces are evaluated before and after wear using scanning electron microscopy (SEM), elemental-dispersive X-ray analysis (EDX), Micro-Vickers hardness test, and contact profilometer. Results show that Group C has the highest hardness value of 1487 ± 126.1 Hv and surface roughness of 1.319 ± 0.3 µm with coefficient of friction being 0.4. SEM analysis revealed that the wear observed on the surfaces of Group B and Group D was due to fatigue rather than abrasion. It was concluded from this study that friction and wear performances of Group A had no visible wear track with coefficient of friction being 0.38 and hardness value of 1408.5 ± 135.4 Hv. These results indicate that Group A and Group C are more favorable for clinical applications. © 2020, Springer Nature Switzerland AG.