Search results for: steel fiber.
465 Three-Phase High Frequency AC Conversion Circuit with Dual Mode PWM/PDM Control Strategy for High Power IH Applications
Authors: Nabil A. Ahmed
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This paper presents a novel three-phase utility frequency to high frequency soft switching power conversion circuit with dual mode pulse width modulation and pulse density modulation for high power induction heating applications as melting of steel and non ferrous metals, annealing of metals, surface hardening of steel and cast iron work pieces and hot water producers, steamers and super heated steamers. This high frequency power conversion circuit can operate from three-phase systems to produce high current for high power induction heating applications under the principles of ZVS and it can regulate its ac output power from the rated value to a low power level. A dual mode modulation control scheme based on high frequency PWM in synchronization with the utility frequency positive and negative half cycles for the proposed high frequency conversion circuit and utility frequency pulse density modulation is produced to extend its soft switching operating range for wide ac output power regulation. A dual packs heat exchanger assembly is designed to be used in consumer and industrial fluid pipeline systems and it is proved to be suitable for the hot water, steam and super heated steam producers. Experiment and simulation results are given in this paper to verify the operation principles of the proposed ac conversion circuit and to evaluate its power regulation and conversion efficiency. Also, the paper presents a mutual coupling model of the induction heating load instead of equivalent transformer circuit model.Keywords: Induction heating, three-phase, conversion circuit, pulse width modulation, pulse density modulation, high frequency, soft switching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2167464 Self-Healing Performance of Heavyweight Concrete with Steam Curing
Authors: Hideki Igawa, Yoshinori Kitsutaka, Takashi Yokomuro, Hideo Eguchi
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In this study, the crack self-healing performance of the heavyweight concrete used in the walls of containers and structures designed to shield radioactive materials was investigated. A steam curing temperature that preserves self-healing properties and demolding strength was identified. The presented simultaneously mixing method using the expanding material and the fly ash in the process of admixture can maximize the self-curing performance. Also adding synthetic fibers in the heavyweight concrete improved the self-healing performance.
Keywords: Expanding material, heavyweight concrete, self-healing performance, synthetic fiber.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1232463 Temperature-Based Detection of Initial Yielding Point in Loading of Tensile Specimens Made of Structural Steel
Authors: Aqsa Jamil, Hiroshi Tamura, Hiroshi Katsuchi, Jiaqi Wang
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Yield point represents the upper limit of forces which can be applied on a specimen without causing any permanent deformation. After yielding, the behavior of specimen suddenly changes including the possibility of cracking or buckling. So, the accumulation of damage or type of fracture changes depending on this condition. As it is difficult to accurately detect yield points of the several stress concentration points in structural steel specimens, an effort has been made in this research work to develop a convenient technique using thermography (temperature-based detection) during tensile tests for the precise detection of yield point initiation. To verify the applicability of thermography camera, tests were conducted under different loading conditions and measuring the deformation by installing various strain gauges and monitoring the surface temperature with the help of thermography camera. The yield point of specimens was estimated by the help of temperature dip which occurs due to the thermoelastic effect during the plastic deformation. The scattering of the data has been checked by performing repeatability analysis. The effect of temperature imperfection and light source has been checked by carrying out the tests at daytime as well as midnight and by calculating the signal to noise ratio (SNR) of the noised data from the infrared thermography camera, it can be concluded that the camera is independent of testing time and the presence of a visible light source. Furthermore, a fully coupled thermal-stress analysis has been performed by using Abaqus/Standard exact implementation technique to validate the temperature profiles obtained from the thermography camera and to check the feasibility of numerical simulation for the prediction of results extracted with the help of thermographic technique.
Keywords: Signal to noise ratio, thermoelastic effect, thermography, yield point.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 345462 Simulation of Soil-Pile Interaction of Steel Batter Piles Penetrated in Sandy Soil Subjected to Pull-Out Loads
Authors: Ameer A. Jebur, William Atherton, Rafid M. Alkhaddar, Edward Loffill
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Superstructures like offshore platforms, tall buildings, transition towers, skyscrapers and bridges are normally designed to resist compression, uplift and lateral forces from wind waves, negative skin friction, ship impact and other applied loads. Better understanding and the precise simulation of the response of batter piles under the action of independent uplift loads is a vital topic and an area of active research in the field of geotechnical engineering. This paper investigates the use of finite element code (FEC) to examine the behaviour of model batter piles penetrated in dense sand, subjected to pull-out pressure by means of numerical modelling. The concept of the Winkler Model (beam on elastic foundation) has been used in which the interaction between the pile embedded depth and adjacent soil in the bearing zone is simulated by nonlinear p-y curves. The analysis was conducted on different pile slenderness ratios (lc⁄d) ranging from 7.5, 15.22 and 30 respectively. In addition, the optimum batter angle for a model steel pile penetrated in dense sand has been chosen to be 20° as this is the best angle for this simulation as demonstrated by other researcher published in literature. In this numerical analysis, the soil response is idealized as elasto-plastic and the model piles are described as elastic materials for the purpose of simulation. The results revealed that the applied loads affect the pullout pile capacity as well as the lateral pile response for dense sand together with varying shear strength parameters linked to the pile critical depth. Furthermore, the pile pull-out capacity increases with increasing the pile aspect ratios.Keywords: Slenderness ratio, soil-pile interaction, winkler model (beam on elastic foundation), pull-out capacity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1615461 Structural Analysis of a Composite Wind Turbine Blade
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The design of an optimised horizontal axis 5-meter-long wind turbine rotor blade in according with IEC 61400-2 standard is a research and development project in order to fulfil the requirements of high efficiency of torque from wind production and to optimise the structural components to the lightest and strongest way possible. For this purpose, a research study is presented here by focusing on the structural characteristics of a composite wind turbine blade via finite element modelling and analysis tools. In this work, first, the required data regarding the general geometrical parts are gathered. Then, the airfoil geometries are created at various sections along the span of the blade by using CATIA software to obtain the two surfaces, namely; the suction and the pressure side of the blade in which there is a hat shaped fibre reinforced plastic spar beam, so-called chassis starting at 0.5m from the root of the blade and extends up to 4 m and filled with a foam core. The root part connecting the blade to the main rotor differential metallic hub having twelve hollow threaded studs is then modelled. The materials are assigned as two different types of glass fabrics, polymeric foam core material and the steel-balsa wood combination for the root connection parts. The glass fabrics are applied using hand wet lay-up lamination with epoxy resin as METYX L600E10C-0, is the unidirectional continuous fibres and METYX XL800E10F having a tri-axial architecture with fibres in the 0,+45,-45 degree orientations in a ratio of 2:1:1. Divinycell H45 is used as the polymeric foam. The finite element modelling of the blade is performed via MSC PATRAN software with various meshes created on each structural part considering shell type for all surface geometries, and lumped mass were added to simulate extra adhesive locations. For the static analysis, the boundary conditions are assigned as fixed at the root through aforementioned bolts, where for dynamic analysis both fixed-free and free-free boundary conditions are made. By also taking the mesh independency into account, MSC NASTRAN is used as a solver for both analyses. The static analysis aims the tip deflection of the blade under its own weight and the dynamic analysis comprises normal mode dynamic analysis performed in order to obtain the natural frequencies and corresponding mode shapes focusing the first five in and out-of-plane bending and the torsional modes of the blade. The analyses results of this study are then used as a benchmark prior to modal testing, where the experiments over the produced wind turbine rotor blade has approved the analytical calculations.
Keywords: Dynamic analysis, Fiber Reinforced Composites, Horizontal axis wind turbine blade, Hand-wet layup, Modal Testing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5001460 Study of Biocomposites Based of Poly(Lactic Acid) and Olive Husk Flour
Authors: Samra Isadounene, Amar Boukerrou, Dalila Hammiche
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In this work, the composites were prepared with poly(lactic acid) (PLA) and olive husk flour (OHF) with different percentages (10, 20 and 30%) using extrusion method followed by injection molding. The morphological, mechanical properties and thermal behavior of composites were investigated. Tensile strength and elongation at break of composites showed a decreasing trend with increasing fiber content. On the other hand, Young modulus and storage modulus were increased. The addition of OHF resulted in a decrease in thermal stability of composites. The presence of OHF led to an increase in percentage of crystallinity (Xc) of PLA matrix.Keywords: Biopolymers, composites, mechanical properties, poly(lactic acid).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 990459 Residual Stress in Ground WC-Co Coatings
Authors: M. Jalali Azizpour, H. Mohammadi Majd
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High velocity oxygen fuel (HVOF) spray technique is one of the leading technologies that have been proposed as an alternative to the replacement of electrolytic hard chromium plating in a number of engineering applications. In this study, WC-Co powder was coated on AISI1045 steel using high velocity oxy fuel (HVOF) method. The sin2ψ method was used to evaluate the through thickness residual stress by means of XRD after mechanical layer removal process (only grinding). The average of through thickness residual stress using X-Ray diffraction was -400 MPa.
Keywords: Grinding, HVOF, Thermal spray, WC-Co.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2709458 A High-Crosstalk Silicon Photonic Arrayed Waveguide Grating
Authors: Qing Fang, Lianxi Jia, Junfeng Song, Chao Li, Xianshu Luo, Mingbin Yu, Guoqiang Lo
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In this paper, we demonstrated a 1 × 4 silicon photonic cascaded arrayed waveguide grating, which is fabricated on a SOI wafer with a 220 nm top Si layer and a 2µm buried oxide layer. The measured on-chip transmission loss of this cascaded arrayed waveguide grating is ~ 5.6 dB, including the fiber-to-waveguide coupling loss. The adjacent crosstalk is 33.2 dB. Compared to the normal single silicon photonic arrayed waveguide grating with a crosstalk of ~ 12.5 dB, the crosstalk of this device has been dramatically increased.
Keywords: Silicon photonic, arrayed waveguide grating, high-crosstalk, cascaded structure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1794457 Experimental Investigation on Mechanical Properties of Rice Husk Filled Jute Reinforced Composites
Authors: Priyankar Pratim Deka, Sutanu Samanta
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This paper describes the development of new class of epoxy based rice husk filled jute reinforced composites. Rice husk flour is added in 0%, 1%, 3%, 5% by weight. Epoxy resin and triethylenetetramine (T.E.T.A) is used as matrix and hardener respectively. It investigates the mechanical properties of the composites and a comparison is done for monolithic jute composite and the filled ones. The specimens are prepared according to the ASTM standards and experimentation is carried out using INSTRON 8801. The result shows that with the increase of filler percentage the tensile properties increases but compressive and flexural properties decreases.Keywords: Jute, mechanical characterization, natural fiber, rice husk.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2050456 Single Spectrum End Point Predict of BOF with SVM
Authors: Ling-fei Xu, Qi Zhao, Yan-ru Chen, Mu-chun Zhou, Meng Zhang, Shi-xue Xu
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SVM ( Support Vector Machine ) is a new method in the artificial neural network ( ANN ). In the steel making, how to use computer to predict the end point of BOF accuracy is a great problem. A lot of method and theory have been claimed, but most of the results is not satisfied. Now the hot topic in the BOF end point predicting is to use optical way the predict the end point in the BOF. And we found that there exist some regular in the characteristic curve of the flame from the mouse of pudding. And we can use SVM to predict end point of the BOF, just single spectrum intensity should be required as the input parameter. Moreover, its compatibility for the input space is better than the BP network.
Keywords: SVM, predict, BOF, single spectrum intensity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1340455 Study on a New Formulation of Domestic Metro Synthetic Brake Shoe
Authors: Yang Chengmei
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In this paper, taking Chinese Nanjing Metro ALSTOM vehicle synthesis brake as an example, the subway with synthetic brake shoe formula components of final product performance, has done a lot of research and performance test, final is drawn with hybrid fiber as reinforcing material, modified phenolic resin as matrix material, and then filling friction modifier performance, by the hot pressing process made a new type of domestic subway brake shoe. The product of the test performance indicators that can replace the similar foreign products.
Keywords: Metro, synthetic brake shoe, component analysis, formula research.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3012454 The Effect of Air Entraining Agents on Compressive Strength
Authors: Demet Yavuz
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Freeze-thaw cycles are one of the greatest threats to concrete durability. Lately, protection against this threat excites scientists’ attention. Air-entraining admixtures have been widely used to produce freeze-thaw resistant at concretes. The use of air-entraining agents (AEAs) enhances not only freeze-thaw endurance but also the properties of fresh concrete such as segregation, bleeding and flow ability. This paper examines the effects of air-entraining on compressive strength of concrete. Air-entraining is used between 0.05% and 0.4% by weight of cement. One control and four fiber reinforced concrete mixes are prepared and three specimens are tested for each mix. It is concluded from the test results that when air entraining is increased the compressive strength of concrete reduces for all mixes with AEAs.
Keywords: Concrete, air-entraining, compressive strength, mechanical properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1741453 Physical and Chemical Investigation of Polycaprolactone, Nanohydroxyapatite and Poly (Vinyl Alcohol) Nanocomposite Scaffolds
Authors: A.Doustgani, E.Vasheghani- Farahani, M. Soleimani, S. Hashemi-Najafabadi
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Aligned and random nanofibrous scaffolds of PVA/PCL/nHA were fabricated by electrospinning method. The composite nanofibrous scaffolds were subjected to detailed analysis. Morphological investigations revealed that the prepared nanofibers have uniform morphology and the average fiber diameters of aligned and random scaffolds were 135.5 and 290 nm, respectively. The obtained scaffolds have a porous structure with porosity of 88 and 76% for random and aligned nanofibers, respectively. Furthermore, FTIR analysis demonstrated that there were strong intramolecular interactions between the molecules of PVA/PCL/nHA. On the other hand, mechanical characterizations show that aligning the nanofibers, could significantly improve the rigidity of the resultant biocomposite nanofibrous scaffolds.
Keywords: Electrospinnig, nanofibrous scaffold, poly (vinyl alcohol), polycaprolactone.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2707452 A Fundamental Study for Real-Time Safety Evaluation System of Landing Pier Using FBG Sensor
Authors: Heungsu Lee, Youngseok Kim, Jonghwa Yi, Chul Park
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A landing pier is subjected to safety assessment by visual inspection and design data, but it is difficult to check the damage in real-time. In this study, real - time damage detection and safety evaluation methods were studied. As a result of structural analysis of the arbitrary landing pier structure, the inflection point of deformation and moment occurred at 10%, 50%, and 90% of pile length. The critical value of Fiber Bragg Grating (FBG) sensor was set according to the safety factor, and the FBG sensor application method for real - time safety evaluation was derived.
Keywords: FBG sensor, harbor structure, maintenance, safety evaluation system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 927451 Implementation of the Recursive Formula for Evaluation of the Strength of Daniels’ Model
Authors: Václav Sadílek, Miroslav Vořechovský
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The paper deals with the classical fiber bundle model of equal load sharing, sometimes referred to as the Daniels’ bundle or the democratic bundle. Daniels formulated a multidimensional integral and also a recursive formula for evaluation of the strength cumulative distribution function. This paper describes three algorithms for evaluation of the recursive formula and also their implementations with source codes in the Python high-level programming language. A comparison of the algorithms are provided with respect to execution time. Analysis of orders of magnitudes of addends in the recursion is also provided.Keywords: Daniels bundle model, equal load sharing, Python, mpmath.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2085450 Polyurethane Nanofibers Obtained By Electrospinning Process
Authors: H. Karakaş, A.S. Saraç, T. Polat, E.G. Budak, S. Bayram, N. Dağ, S. Jahangiri
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Electrospinning is a broadly used technology to obtain polymeric nanofibers ranging from several micrometers down to several hundred nanometers for a wide range of applications. It offers unique capabilities to produce nanofibers with controllable porous structure. With smaller pores and higher surface area than regular fibers, electrospun fibers have been successfully applied in various fields, such as, nanocatalysis, tissue engineering scaffolds, protective clothing, filtration, biomedical, pharmaceutical, optical electronics, healthcare, biotechnology, defense and security, and environmental engineering. In this study, polyurethane nanofibers were obtained under different electrospinning parameters. Fiber morphology and diameter distribution were investigated in order to understand them as a function of process parameters.Keywords: Electrospinning, polyurethane, nanofibers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4783449 A Current Problem for Steel Bridges: Fatigue Assessment of Seams´ Repair
Authors: H. Pasternak, A. Chwastek
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The paper describes the results from a research project about repair of welds. The repair was carried out by grinding the flawed seams and re-welding them. The main task was to determine the FAT classes of original state and after repair of seams according to the assessment procedures, such as nominal, structural and effective notch stress approach. The first part shows the results of the tests, the second part encloses numerical analysis and evaluation of results to determine the fatigue strength classes according to three assessment procedures.
Keywords: Cyclic loading, fatigue crack, post-weld treatment, seams’ repair.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 946448 Statistical Analysis of Different Configurations of Hybrid Doped Fiber Amplifiers
Authors: Inderpreet Kaur, Neena Gupta
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Wavelength multiplexing (WDM) technology along with optical amplifiers is used for optical communication systems in S-band, C-band and L-band. To improve the overall system performance Hybrid amplifiers consisting of cascaded TDFA and EDFA with different gain bandwidths are preferred for long haul wavelength multiplexed optical communication systems. This paper deals with statistical analysis of different configuration of hybrid amplifier i.e. analysis of TDFA-EDFA configuration and EDFA – TDFA configuration. In this paper One-Way ANOVA method is used for statistical analysis.Keywords: WDM, EDFA, TDFA, hybrid amplifier, One-wayANOVA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1851447 Non-Circular Carbon Fiber Reinforced Polymers Chainring Failure Analysis
Authors: A. Elmikaty, Z. Thanawarothon, L. Mezeix
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This paper presents a finite element model to simulate the teeth failure of non-circular composite chainring. Model consists of the chainring and a part of the chain. To reduce the size of the model, only the first 11 rollers are simulated. In order to validate the model, it is firstly applied to a circular aluminum chainring and evolution of the stress in the teeth is compared with the literature. Then, effect of the non-circular shape is studied through three different loading positions. Strength of non-circular composite chainring and failure scenario is investigated. Moreover, two composite lay-ups are proposed to observe the influence of the stacking. Results show that composite material can be used but the lay-up has a large influence on the strength. Finally, loading position does not have influence on the first composite failure that always occurs in the first tooth.
Keywords: CFRP, composite failure, FEA, non-circular chainring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1158446 Behavior of Composite Timber-Concrete Beam with CFRP Reinforcement
Authors: O. Vlcek
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The paper deals with current issues in research of advanced methods to increase reliability of traditional timber structural elements. It analyses the issue of strengthening of bent timber beams, such as ceiling beams in old (historical) buildings with additional concrete slab in combination with externally bonded fiber - reinforced polymer. The study evaluates deflection of a selected group of timber beams with concrete slab and additional CFRP reinforcement using different calculating methods and observes differences in results from different calculating methods. An elastic (EN 1995) calculation method and evaluation with FEM analysis software were used.
Keywords: Timber-concrete composite, strengthening, fibre-reinforced polymer, theoretical analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1791445 Quality of Donut Supplemented with Hom Nin Rice Flour
Authors: Supatchalee Sirichokworrakit, Pannin Intasen, Chansuda Angkawut
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Hom Nin rice (Oryza Sativa L.) was processed into flour and used to substitute wheat flour in donuts. The donuts were prepared with 0, 20, 40, 60, and 80% Hom Nin rice flour (HNF). The donuts were subjected to proximate, texture, color and sensory evaluations. The results of the study revealed that the ash, moisture, crude fiber contents increased while crude fat and protein contents decreased as the level of HNF increased. The hardness and chewiness of donut increased as the HNF increased but the cohesiveness, springiness, and specific volume decreased. Color of donut (L*, a*, and b* values) decreased with the addition of HNF. Overall acceptability for the 20-40% HNF additions did not differ significantly from the score of the 100% wheat flour.Keywords: Hom Nin rice, donut, texture evaluation, sensory evaluation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1887444 Vertical Micromirror Fabrication by X-ray Lithography for Single Mode Optical Fiber Switching Applications
Authors: R. Chimchang, R. Tongta, R. Phatthanakun
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Inthis paper, design and fabrication of vertical micromirror for optical switching applications of single mode optical fibers are proposed. The structure of micromirror will be created from negative photoresist (SU-8) on X-ray lithography using X-ray from synchrotron light source. The properties of X-ray from synchrotron light source are high-energy electrons which can construct materials that have a high aspect ratio. In addition, the technique of gold coating of reflective material has been used for change direction of light between two pairs of optical fibers. At a wavelength of 1310 nm with minimum average loss of 5.305 dB is obtained.Keywords: vertical micromirror, negative photoresist, X-ray lithography
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1585443 Effect of Jet Diameter on Surface Quenching at Different Spatial Locations
Authors: C. Agrawal, R. Kumar, A. Gupta, B. Chatterjee
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An experimental investigation has been carried out to study the cooling of a hot horizontal Stainless Steel surface of 3 mm thickness, which has 800±10 C initial temperature. A round water jet of 22 ± 1 oC temperature was injected over the hot surface through straight tube type nozzles of 2.5- 4.8 mm diameter and 250 mm length. The experiments were performed for the jet exit to target surface spacing of 4 times of jet diameter and jet Reynolds number of 5000 -24000. The effect of change in jet Reynolds number on the surface quenching has been investigated form the stagnation point to 16 mm spatial location.
Keywords: Hot-Surface, Jet Impingement, Quenching, Stagnation Point.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2285442 Influence of Sodium Acetate on Electroless Ni-P Deposits and Effect of Heat Treatment on Corrosion Behavior
Authors: Y. El Kaissi, M. Allam, A. Koulou, M. Galai, M. Ebn Touhami
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The aim of our work is to develop an industrial bath of nickel alloy deposit on mild steel. The optimization of the operating parameters made it possible to obtain a stable Ni-P alloy deposition formulation. To understand the reaction mechanism of the deposition process, a kinetic study was performed by cyclic voltammetry and by electrochemical impedance spectroscopy (EIS). The coatings obtained have a very high corrosion resistance in a very aggressive acid medium which increases with the heat treatment.
Keywords: Ni–P coating, electrochemical impedance spectroscopy, heat treatment, cyclic voltammetry, potentiodynamic polarization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1232441 Preliminary Evaluation of Decommissioning Wastes for the First Commercial Nuclear Power Reactor in South Korea
Authors: Kyomin Lee, Joohee Kim, Sangho Kang
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The commercial nuclear power reactor in South Korea, Kori Unit 1, which was a 587 MWe pressurized water reactor that started operation since 1978, was permanently shut down in June 2017 without an additional operating license extension. The Kori 1 Unit is scheduled to become the nuclear power unit to enter the decommissioning phase. In this study, the preliminary evaluation of the decommissioning wastes for the Kori Unit 1 was performed based on the following series of process: firstly, the plant inventory is investigated based on various documents (i.e., equipment/ component list, construction records, general arrangement drawings). Secondly, the radiological conditions of systems, structures and components (SSCs) are established to estimate the amount of radioactive waste by waste classification. Third, the waste management strategies for Kori Unit 1 including waste packaging are established. Forth, selection of the proper decontamination and dismantling (D&D) technologies is made considering the various factors. Finally, the amount of decommissioning waste by classification for Kori 1 is estimated using the DeCAT program, which was developed by KEPCO-E&C for a decommissioning cost estimation. The preliminary evaluation results have shown that the expected amounts of decommissioning wastes were less than about 2% and 8% of the total wastes generated (i.e., sum of clean wastes and radwastes) before/after waste processing, respectively, and it was found that the majority of contaminated material was carbon or alloy steel and stainless steel. In addition, within the range of availability of information, the results of the evaluation were compared with the results from the various decommissioning experiences data or international/national decommissioning study. The comparison results have shown that the radioactive waste amount from Kori Unit 1 decommissioning were much less than those from the plants decommissioned in U.S. and were comparable to those from the plants in Europe. This result comes from the difference of disposal cost and clearance criteria (i.e., free release level) between U.S. and non-U.S. The preliminary evaluation performed using the methodology established in this study will be useful as a important information in establishing the decommissioning planning for the decommissioning schedule and waste management strategy establishment including the transportation, packaging, handling, and disposal of radioactive wastes.
Keywords: Characterization, classification, decommissioning, decontamination and dismantling, Kori 1, radioactive waste.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1461440 All-Optical Function Based on Self-Similar Spectral Broadening for 2R Regeneration in High-Bit-Rate Optical Transmission Systems
Authors: Leila Graini
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In this paper, we demonstrate basic all-optical functions for 2R regeneration (Re-amplification and Re-shaping) based on self-similar spectral broadening in low normal dispersion and highly nonlinear fiber (ND-HNLF) to regenerate the signal through optical filtering including the transfer function characteristics, and output extinction ratio. Our approach of all-optical 2R regeneration is based on those of Mamyshev. The numerical study reveals the self-similar spectral broadening very effective for 2R all-optical regeneration; the proposed design presents high stability compared to a conventional regenerator using SPM broadening with reduction of the intensity fluctuations and improvement of the extinction ratio.
Keywords: All-optical function, 2R optical regeneration, self-similar broadening, Mamyshev regenerator.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 812439 Numerical Analysis of Fractured Process in Locomotive Steel Wheels
Authors: J. Alizadeh K., R. S. Ashofteh, A. Asadi Lari
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Railway vehicle wheels are designed to operate in harsh environments and to withstand high hydrostatic contact pressures. This situation may result in critical circumstances, in particular wheel breakage. This paper presents a time history of a series of broken wheels during a time interval [2007-2008] belongs to locomotive fleet on Iranian Railways. Such fractures in locomotive wheels never reported before. Due to the importance of this issue, a research study has been launched to find the potential reasons of this problem. The authors introduce a FEM model to indicate how and where the wheels could have been affected during their operation. Then, the modeling results are presented and discussed in detail.
Keywords: Crack, fatigue, FE analysis, wheel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2348438 Separation of CO2 Using MFI-Alumina Nanocomposite Hollow Fiber Ion-Exchanged with Alkali Metal Cation
Authors: A. Alshebani, Y. Swesi, S. Mrayed, F. Altaher, I. Musbah
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Cs-type nanocomposite zeolite membrane was successfully synthesized on an alumina ceramic hollow fibre with a mean outer diameter of 1.7 mm; cesium cationic exchange test was carried out inside test module with mean wall thickness of 230 μm and an average crossing pore size smaller than 0.2 μm. Separation factor of n-butane/H2 obtained indicate that a relatively high quality closed to 20. Maxwell-Stefan modeling provides an equivalent thickness lower than 1 µm. To compare the difference an application to CO2/N2 separation has been achieved, reaching separation factors close to (4,18) before and after cation exchange on H-zeolite membrane formed within the pores of a ceramic alumina substrate.
Keywords: MFI membrane, nanocomposite, Ceramic hollow fibre, CO2, Ion-exchange.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2008437 Effect of Needle Diameter on the Morphological Structure of Electrospun n-Bi2O3/Epoxy-PVA Nanofiber Mats
Authors: Bassam M. Abunahel, Nurul Zahirah Noor Azman, Munirah Jamil
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The effect of needle diameter on the morphological structure of electrospun n-Bi2O3/epoxy-PVA nanofibers has been investigated using three different types of needle diameters. The results were observed and investigated using two techniques of scanning electron microscope (SEM). The first technique is backscattered SEM while the second is secondary electron SEM. The results demonstrate that there is a correlation between the needle diameter and the morphology of electrospun nanofibers. As the internal needle diameter decreases, the average nanofiber diameter decreases and the fibers get thinner and smoother without agglomeration or beads formation. Moreover, with small needle diameter the nanofibrous porosity get larger compared with large needle diameter.
Keywords: Needle diameter, fiber diameter, agglomeration, porosity, SEM.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 998436 Influence of Some Technological Parameters on the Content of Voids in Composite during On-Line Consolidation with Filament Winding Technology
Authors: M. Stefanovska, B. Samakoski, S. Risteska, G. Maneski
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In this study was performed in situ consolidation of polypropylene matrix/glass reinforced roving by combining heating systems and roll pressing. The commingled roving during hoop winding was winded on a cylindrical mandrel. The work also presents the advances made in the processing of these materials into composites by conventional technique filament winding. Experimental studies were performed with changing parameters – temperature, pressure and speed. Finally, it describes the investigation of the optimal processing conditions that maximize the mechanical properties of the composites. These properties are good enough for composites to be used as engineering materials in many structural applications.
Keywords: Commingled fiber, consolidation heat, filament winding, voids.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2361