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Comparative structural analysis of lattice hybrid and tubular wind turbine towers
R. Kumaravel,A. Krishnamoorthy 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.30 No.1
This paper presents a comparative structural analysis of lattice hybrid tower with six legs with conventional tubular steel tower for an onshore wind turbine using finite element method. Usually a lattice hybrid tower will have a conventional industry standard \'L\' profile section for the lattice construction with four legs. In this work, the researcher attempted to identify and analyze the strength of six legged lattice hybrid tower designed with a special profile instead of four legged L profile. And to compare the structural benefits of special star profile with the conventional tubular tower. Using Ansys, a commercial FEM software, both static and dynamic structural analyses were performed. A simplified finite element model that represents the wind turbine tower was created using Shell elements. An ultimate load condition was applied to check the stress level of the tower in the static analysis. For the dynamic analysis, the frequency extraction was performed in order to obtain the natural frequencies of the tower.
Electronic Structure of Nano-Sized ZnO: A Compton Profile Study
R. Kumaravel,M. C. Mishra,B. K. Sharma,V. Vyas,G. Sharma 대한금속·재료학회 2013 ELECTRONIC MATERIALS LETTERS Vol.9 No.1
The electronic structure of nano-sized ZnO using Compton scattering technique is reported. The nano-crystalline ZnO of size 10.5 nm is synthesized using the chemical route and characterized by XRD, SEM, TEM probes. Using 59.54 keV gamma-rays, the Compton profile measurements are performed on nano-sized as well as bulk ZnO. The present study reveals the narrower electron momentum density in nano-sized ZnO as compared to bulk sample. The ionic model based free atom Compton profiles for a number of configurations of Zn+xO−x (0.0 ≤ x ≤ 2.0) are also performed to estimate the charge transfer on compound formation. The present study suggests different amount of charge transfer from Zn to O atom in the nano-sized and bulk ZnO.
Preparation of cadmium stannate films by spray pyrolysis technique
V. Krishnakumar,K. Ramamurthi,R. Kumaravel,K. Santhakumar 한국물리학회 2009 Current Applied Physics Vol.9 No.3
Cadmium stannate thin films were prepared by spray pyrolysis technique using cadmium acetate and tin(Ⅱ) chloride precursors at substrate temperatures 450℃ and 500 ℃. XRD pattern confirms the formation of orthorhombic (111) cadmium stannate phase for the film prepared at substrate temperature of 500 ℃, whereas, films prepared at 450 ℃ are morphous. Film formation does not occur at substrate temperature from 300 to 375 ℃. SEM images reveal that the surface of the prepared Cd2SnO4 film is smooth. The average optical transmittance of ~86% is obtained for the film prepared at substrate temperature of 500 ℃ with the film thickness of 400 nm. The optical band gap value of the films varies from 2.7 to 2.94 eV. The film prepared at 500 ℃ shows a minimum resistivity of 35.6 × 10-4 Ωcm. Cadmium stannate thin films were prepared by spray pyrolysis technique using cadmium acetate and tin(Ⅱ) chloride precursors at substrate temperatures 450℃ and 500 ℃. XRD pattern confirms the formation of orthorhombic (111) cadmium stannate phase for the film prepared at substrate temperature of 500 ℃, whereas, films prepared at 450 ℃ are morphous. Film formation does not occur at substrate temperature from 300 to 375 ℃. SEM images reveal that the surface of the prepared Cd2SnO4 film is smooth. The average optical transmittance of ~86% is obtained for the film prepared at substrate temperature of 500 ℃ with the film thickness of 400 nm. The optical band gap value of the films varies from 2.7 to 2.94 eV. The film prepared at 500 ℃ shows a minimum resistivity of 35.6 × 10-4 Ωcm.
T. Immanuvel David,M. V. Mukesh,S. Kumaravel,G. Ramesh,R. Premkumar 대한공간정보학회 2017 Spatial Information Research Vol.25 No.4
Land use land cover (LU/LC) changes over the period are essential to understand the development of human activities within a region to define the impact of anthropogenic and natural activities. The virtual assessment of LU/LC changes between 2000 and 2016 is carried out in Pearl City (Thoothukudi) using Remote-Sensing data and GIS tool. This change detection is done by 15 m resolution cloud-free Advanced Spaceborne Thermal Emission and Reflection Radiometer data captured during the year 2000 and 2016. The dynamic changes depict the major land use features like settlements, saltpan, crop land, vegetation, barren and water body from satellite data through supervised classifications of a maximum likelihood algorithm. The classified images highlight a series of constructive results in settlement (4.30%), vegetation (4.00%), saltpan (0.24%) and pessimistic results in barren land (-7.68%), crop land (-0.64%) and water body (-0.23%) respectively. The study recommends that urbanization of settlement land usage is highly mobilized in Thoothukudi coastal areas.