Behavior of CFRP Strengthened CHS under Axial Static and Axial Cyclic Loading

A. Punitha Kumar,R. Senthil 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.4

Fibre Reinforced Polymer (FRP) wrapping is one of the techniques used to strengthen the concrete structures. Recently these techniques are implemented for the strengthening of steel structures. This study emphasizes on experimental investigation of Carbon Fibre Reinforced Polymer (CFRP) strengthened steel hollow sections under axial static and axial cyclic loading. In CFRP strengthened steel hollow section, number of layers and orientation of layers are the key factors for the prediction of axial capacity. A series of tests were conducted on CFRP strengthened steel Circular Hollow Sections (CHS) by varying the number and orientation of the CFRP layers under axial static and axial cyclic loading. From the experimental results, it was observed that the strength, ductility and stiffness has increased in the CFRP strengthened specimens. The results highlight that the axial load carrying capacity of CFRP strengthened circular hollow steel section has been increased up to 37.13% in static loading and 42.86% in axial cyclic loading. CFRP confinement could be responsible for the increase in the axial capacity of steel hollow section and this method could be used to enhance the performance of existing steel hollow sections.

Experimental investigations of Co3O4, SiO2, cotton seed oil additive blends in the diesel engine and optimization by ANN-SVM process

A.P. Senthil Kumar,S. Yuvaraj,S. Janaki 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.2

The demand for alternative fuel replaces the pure utilization of diesel fuel in the engines. Nano additives and the biodiesel areintroduced as the additives for reducing the emission characteristics and fulfil the energy requirements. The main objectiveof this research is to determine the emission characteristics of metal additives and cottonseed added diesel. Three combinationsof cobalt oxide contributeto the fuel blend preparation, namely, cobalt oxide + cottonseed oil, Cobalt oxide + silicon oxide andseparate cobalt oxide in the diesel fuel. Such combinations are mixed in the diesel fuel by adopting the method of ultrasonicdispersed technique with three different proportions such as 25 ppm, 50 ppm and 100 ppm of Nano additives and B20, B40and B60 blends of cottonseed oil. The strategy of Artificial Neural Network-Support Vector Machine (ANN-SVM) is appliedto optimize and predict the better-reduced emission characteristics of CO, HC and NOx through the mat lab platform. Thetesting is carried out with five different load conditions such as 0, 25, 50, 75 and 100 N and a constant compression ratio 17.5. Terminally, the comparison between predicted and experimented values are also presented for determining the better cobaltoxide fuel blend combinations with minimum emission outflow. The combination of both additives such as silicon oxide andthe cobalt oxide proceeds better emission characteristics from both the predicted and the experimented outcomes. In which,the predicted outcomes are 64.1% of NOx, 0.018% of CO and 1.610% of HC.

Carbon sphere: Synthesis, characterization and elimination of toxic Cr(VI) ions from aquatic system

P. Senthil Kumar,R. Sivaranjanee,P. Sundar Rajan,A. Saravanan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.60 No.-

Carbon sphere has been newly prepared for the ejection of Cr(VI) ions. SEM-EDX, XRD and FTIR reports affirmed its quality. Trial and error analysis has been embraced to advance the system conditions. Langmuir maximum adsorption capacity (117.2 mg/g) was achieved at a pH of 2, adsorbent dosage of 4 g/L, contact time of 60 min and temperature of 30 °C for an initial Cr(VI) ion concentration of 50–500 mg/L. Adsorption process was controlled by surface diffusion. Pseudo-second order model was the best obeyed model. An exothermic and unconstrained sorption process was observed. Sticking probability explained that adsorption was favoured at low temperature.

Finite element analysis of functionally graded sandwich plates under nonlinear sense for aerospace applications

M.N.A. GulshanTaj,Anupam Chakrabarti,R. Malathy,S.R.R. Senthil Kumar 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.80 No.3

Owing to the increase in demand for composite materials for different applications in aircraft structures, the nonlinear response of functionally graded ceramic-metal sandwich plates under mechanical loading is studied in the present research work. Geometric nonlinearity (GNL) is considered by Green-strain components and further assumes the form of von Kármán strains. It is ascertained that the effective mechanical properties vary through the thickness direction as a function of volume fraction of ceramic and metal constituents and obeys power law equation. Higher order displacement model proposed by Reddy is incorporated in the study to arrive for 2D isoparametric finite element C0 formulation. A nine node Lagrangian element is accomplished to model the assumed plate geometry. Different thickness schemes are proposed to model the sandwich plate with graded layer as core/ face sheets. Although the model can handle thickness scheme of any kind, results are exposed for four types of symmetric sandwich plates. Comparison statement between isotropic and graded plates is drawn in each case by appropriate selection of power law exponent value. The present investigation may be useful for design engineers/researchers to arrive for particular thickness scheme based on the results, while performing large deformation analysis of functionally graded sandwich plates (FGSP).

Roll-to-Roll Embossing of Optical Radial Fresnel Lenses on Polymer Film for Concentrator Photovoltaics: A Feasibility Study

Rui Huang,Xinquan Zhang,Boon Ping Ng,A. Senthil Kumar,Kui Liu 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.1

Fresnel-based concentrated photovoltaic (CPV) solar power systems have been proven effective to significantly enhance the photoelectric conversion efficiency, but a standard-size solar plant will require an extremely large amount of polymer radial Fresnel lenses. Roll-to-roll (R2R) manufacturing is a high-throughput technology to mass produce high-quality functional optical polymer fi lm. In this paper, we have firstly studied a complete manufacturing cycle for R2R embossing of radial Fresnel lens polymer fi lm for CPV systems, in terms of polymer lens design, roller mold machining, R2R embossing and optical performance test. Instead of wrapping an electroplated metal sheet onto the roller in conventional R2R process, the lens pattern array is directly machined using a 5-axis ultra-precision machining system to guarantee its surface quality and accuracy. Optical performance evaluation for the manufactured polymer fi lm using a reference solar cell is conducted, and results have shown that radial Fresnel lens on the polymer fi lm can achieve a sunlight concentration ratio 3.9 × times that of linear lenses with a much smaller receiving area. This study has explored the feasibility for R2R embossing of optical polymer fi lm, an industry-applicable and cost-effective technology for mass production of high-quality Fresnel lenses to be used in high-efficiency CPV systems.

Multi-response optimization of crashworthiness parameters of bi-tubular structures

K. Vinayagar,A. Senthil Kumar 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.23 No.1

This article aims at presenting multi objective optimization of parameters that affect crashworthiness characteristics of bi-tubular structures using Taguchi method with grey relational analysis. To design the experiments, the <i>L</i>₉ orthogonal array has been used and based on that, the inner tubes have been fabricated by varying the three influence factors such as reference diameter, length difference and numbers of sides of the polygon with three levels, but all the outer cylinders have the same diameter and length 90 mm and 135 mm respectively. Then, the tailor made bi-tubular steel structures were subjected into quasi static axial compression. From the test results it is found that the crushing behaviors of bi-tubular structures with different combinations were fairly significant. The important responses (crashworthiness indicators) specific energy absorption and crush force efficiency have been evaluated from load - displacement curve. Finally optimal levels of parameters were identified using grey relational analysis, and significance of parameters was determined by analysis of variance. The optimum crashworthiness parameters are reference diameter 80 mm, length difference 0 mm and number of sides of polygon is 3, i.e., triangle within the selected nine bi-tube combinations.

1P-706 Effect of inherent residual chloride and degree of hydration on the electron-transfer activity of RuO₂

( K. Chandrasekara Pillai ),( A. Senthil Kumar ),문일식 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

Despite the unparalleled extensive use of ruthenium dioxide (RuO₂), in both crystalline and amorphous forms, in a wide range of electrochemical applications, the intrinsic electron-transfer (ET) rate constant estimations at RuO₂ electrodes prepared at different temperatures are not reported in detail. In this paper, the ET rate constants for RuO₂ electrodes are estimated by rotating disk electrode (RDE) technique using an oxide-sensitive, non-interacting Fe³⁺/Fe²⁺ redox probe. Chemically modified RuO₂ electrodes using oxide powders assembled on Pt support using polyvinylchloride binder are used. RuO2 powders prepared at five temperatures, 300 to 700°C, are studied to investigate the dependence of ET activity of electrodes on the oxide preparation temperature.

Modelling and analysis on the removal of methylene blue dye from aqueous solution using physically/chemically modified Ceiba pentandra seeds

G. Manikandan,P. Senthil Kumar,A. Saravanan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.62 No.-

In this research, batch adsorptions of methylene blue (MB) dye using physically and chemically activated Ceiba pentandra seeds (PACP and CACP) have been inspected. SEM-EDAX and XRD analysis for adsorbents have been studied. The acquired consequences of isotherm and kinetic investigations exhibit that Freundlich and pseudo-first order models demonstrated better association. Langmuir adsorption capacity of PACP and CACP was observed as 324.01 and 469.4 mg/g, respectively. Sticking probability for MB dye was found to be high. This adsorption process was unconstrained and exothermic in nature. This modified materials has an ability to remove MB dye from polluted water.

Molecular characterization of chromium resistant gram-negative bacteria isolated from industrial effluent: Bioremedial activity

P.R. Yaashikaa,P. Senthil Kumar,A. Saravanan 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-

Hexavalent chromium has negative effect on the ecosystem and the aim is to molecularly characterize thebacteria that have high potential for detoxifying hexavalent chromium in tannery effluents. Onepredominant isolate identified was able to grow on medium with the hexavalent chromiumconcentrations of 2200 mg/L. The resistant isolate was identified as Pannonibacter phragmitetus after16S rRNA gene sequencing and annotation has been submitted in NCBI GenBank. The 3D protein structurewas modeled using I-TASSER. The results of chromium degrading ability evaluated using AtomicAbsorption Spectrophotometer showed that the isolate can be applied as potential bioremediation agentfor chromium removal.

Ultrasonic modified corn pith for the sequestration of dye from aqueous solution

R. Jothirani,P. Senthil Kumar,A. Saravanan,Abishek S. Narayan,Abhishek Dutta 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.39 No.-

In this research, the ultrasonic waves were used to prepare the novel material from corn pith for theremoval of malachite green (MG) dye from aqueous solution. The prepared material was characterizedby BET, FTIR, SEM, TGA and XRD analyses. Adsorption system followed Freundlich and pseudo-first orderkinetic models. Langmuir monolayer capacity of the adsorbent was calculated as 488.3 mg g 1 whichwas higher as compared with other local materials. Adsorption thermodynamics was found to beexothermic and spontaneous. The adsorber was designed using Freundlich model. The novel materialshowed good adsorption capacity for sequestration of MG dye from wastewater.