Search results for: non-linear thermal radiation
2614 Thermal Properties of the Ground in Cyprus and Their Correlations and Effect on the Efficiency of Ground Heat Exchangers
Authors: G. A. Florides, E. Theofanous, I. Iosif-Stylianou, P. Christodoulides, S. Kalogirou, V. Messarites, Z. Zomeni, E. Tsiolakis, P. D. Pouloupatis, G. P. Panayiotou
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Ground Coupled Heat Pumps (GCHPs) exploit effectively the heat capacity of the ground, with the use of Ground Heat Exchangers (GHE). Depending on the mode of operation of the GCHPs, GHEs dissipate or absorb heat from the ground. For sizing the GHE the thermal properties of the ground need to be known. This paper gives information about the density, thermal conductivity, specific heat and thermal diffusivity of various lithologies encountered in Cyprus with various relations between these properties being examined through comparison and modeling. The results show that the most important correlation is the one encountered between thermal conductivity and thermal diffusivity with both properties showing similar response to the inlet and outlet flow temperature of vertical and horizontal heat exchangers.
Keywords: Ground heat exchangers, ground thermal conductivity, ground thermal diffusivity, ground thermal properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18652613 Analysis of Conduction-Radiation Heat Transfer in a Planar Medium: Application of the Lattice Boltzmann Method
Authors: Ahmed Mahmoudi, Imen Mejri, Mohamed A. Abbassi, Ahmed Omri
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In this paper, the 1-D conduction-radiation problem is solved by the lattice Boltzmann method. The effects of various parameters such as the scattering albedo, the conduction–radiation parameter and the wall emissivity are studied. In order to check on the accuracy of the numerical technique employed for the solution of the considered problem, the present numerical code was validated with the published study. The found results are in good agreement with those published
Keywords: Conduction, lattice Boltzmann method, planar medium, radiation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25272612 Effect of Implementation of Nonlinear Sequence Transformations on Power Series Expansion for a Class of Non-Linear Abel Equations
Authors: Javad Abdalkhani
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Convergence of power series solutions for a class of non-linear Abel type equations, including an equation that arises in nonlinear cooling of semi-infinite rods, is very slow inside their small radius of convergence. Beyond that the corresponding power series are wildly divergent. Implementation of nonlinear sequence transformation allow effortless evaluation of these power series on very large intervals..Keywords: Nonlinear transformation, Abel Volterra Equations, Mathematica
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12632611 Thermal Analysis of Photovoltaic Integrated Greenhouse Solar Dryer
Authors: Sumit Tiwari, Rohit Tripathi, G. N. Tiwari
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Present study focused on the utilization of solar energy by the help of photovoltaic greenhouse solar dryer under forced mode. A single slope photovoltaic greenhouse solar dryer has been proposed and thermal modelling has been developed. Various parameters have been calculated by thermal modelling such as greenhouse room temperature, cell temperature, crop temperature and air temperature at exit of greenhouse. Further cell efficiency, thermal efficiency, and overall thermal efficiency have been calculated for a typical day of May and November. It was found that system can generate equivalent thermal energy up to 7.65 kW and 6.66 kW per day for clear day of May and November respectively.Keywords: Characteristics curve, Photovoltaic, Thermal modelling, Thermal efficiency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24692610 A Modification on Newton's Method for Solving Systems of Nonlinear Equations
Authors: Jafar Biazar, Behzad Ghanbari
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In this paper, we are concerned with the further study for system of nonlinear equations. Since systems with inaccurate function values or problems with high computational cost arise frequently in science and engineering, recently such systems have attracted researcher-s interest. In this work we present a new method which is independent of function evolutions and has a quadratic convergence. This method can be viewed as a extension of some recent methods for solving mentioned systems of nonlinear equations. Numerical results of applying this method to some test problems show the efficiently and reliability of method.
Keywords: System of nonlinear equations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15442609 Influence of Thermal Cycle on Temperature Dependent Process Parameters Involved in GTA Welded High Carbon Steel Joints
Authors: J. Dutta, Narendranath S.
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In this research article a comprehensive investigation has been carried out to determine the effect of thermal cycle on temperature dependent process parameters developed during gas tungsten arc (GTA) welding of high carbon (AISI 1090) steel butt joints. An experiment based thermal analysis has been performed to obtain the thermal history. We have focused on different thermophysical properties such as thermal conductivity, heat transfer coefficient and cooling rate. Angular torch model has been utilized to find out the surface heat flux and its variation along the fusion zone as well as along the longitudinal direction from fusion boundary. After welding and formation of weld pool, heat transfer coefficient varies rapidly in the vicinity of molten weld bead and heat affected zone. To evaluate the heat transfer coefficient near the fusion line and near the rear end of the plate (low temperature region), established correlation has been implemented and has been compared with empirical correlation which is noted as coupled convective and radiation heat transfer coefficient. Change in thermal conductivity has been visualized by analytical model of moving point heat source. Rate of cooling has been estimated by using 2-dimensional mathematical expression of cooling rate and it has shown good agreement with experimental temperature cycle. Thermophysical properties have been varied randomly within 0 -10s time span.
Keywords: Thermal history, Gas tungsten arc welding, Butt joint, High carbon steel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27202608 On the Approximate Solution of a Nonlinear Singular Integral Equation
Authors: Nizami Mustafa, C. Ardil
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In this study, the existence and uniqueness of the solution of a nonlinear singular integral equation that is defined on a region in the complex plane is proven and a method is given for finding the solution.
Keywords: Approximate solution, Fixed-point principle, Nonlinear singular integral equations, Vekua integral operator
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18722607 Thermal Fatigue Behavior of 400 Series Ferritic Stainless Steels
Authors: Seok Hong Min, Tae Kwon Ha
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In this study, thermal fatigue properties of 400 series ferritic stainless steels have been evaluated in the temperature ranges of 200-800oC and 200-900oC. Systematic methods for control of temperatures within the predetermined range and measurement of load applied to specimens as a function of temperature during thermal cycles have been established. Thermal fatigue tests were conducted under fully constrained condition, where both ends of specimens were completely fixed. It has been revealed that load relaxation behavior at the temperatures of thermal cycle was closely related with the thermal fatigue property. Thermal fatigue resistance of 430J1L stainless steel is found to be superior to the other steels.Keywords: Ferritic stainless steel, automotive exhaust, thermal fatigue, microstructure, load relaxation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20792606 Buildings Founded on Thermal Insulation Layer Subjected to Earthquake Load
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The modern energy-efficient houses are often founded on a thermal insulation (TI) layer placed under the building’s RC foundation slab.The purpose of the paper is to identify the potential problems of the buildings founded on TI layer from the seismic point of view. The two main goals of the study were to assess the seismic behavior of such buildings, and to search for the critical structural parameters affecting the response of the superstructure as well as of the extruded polystyrene (XPS) layer. As a test building a multi-storeyed RC frame structure with and without the XPS layer under the foundation slab has been investigated utilizing nonlinear dynamic (time-history) and static (pushover) analyses. The structural response has been investigated with reference to the following performance parameters: i) Building’s lateral roof displacements, ii) Edge compressive and shear strains of the XPS, iii) Horizontal accelerations of the superstructure, iv) Plastic hinge patterns of the superstructure, v) Part of the foundation in compression, and vi) Deformations of the underlying soil and vertical displacements of the foundation slab (i.e. identifying the potential uplift). The results have shown that in the case of higher and stiff structures lying on firm soil the use of XPS under the foundation slab might induce amplified structural peak responses compared to the building models without XPS under the foundation slab. The analysis has revealed that the superstructure as well as the XPS response is substantially affected by the stiffness of the foundation slab.
Keywords: Extruded polystyrene (XPS), foundation on thermal insulation, energy-efficient buildings, nonlinear seismic analysis, seismic response, soil–structure interaction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21802605 Some Third Order Methods for Solving Systems of Nonlinear Equations
Authors: Janak Raj Sharma, Rajni Sharma
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Based on Traub-s methods for solving nonlinear equation f(x) = 0, we develop two families of third-order methods for solving system of nonlinear equations F(x) = 0. The families include well-known existing methods as special cases. The stability is corroborated by numerical results. Comparison with well-known methods shows that the present methods are robust. These higher order methods may be very useful in the numerical applications requiring high precision in their computations because these methods yield a clear reduction in number of iterations.Keywords: Nonlinear equations and systems, Newton's method, fixed point iteration, order of convergence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21532604 State Estimation Method Based on Unscented Kalman Filter for Vehicle Nonlinear Dynamics
Authors: Wataru Nakamura, Tomoaki Hashimoto, Liang-Kuang Chen
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This paper provides a state estimation method for automatic control systems of nonlinear vehicle dynamics. A nonlinear tire model is employed to represent the realistic behavior of a vehicle. In general, all the state variables of control systems are not precisedly known, because those variables are observed through output sensors and limited parts of them might be only measurable. Hence, automatic control systems must incorporate some type of state estimation. It is needed to establish a state estimation method for nonlinear vehicle dynamics with restricted measurable state variables. For this purpose, unscented Kalman filter method is applied in this study for estimating the state variables of nonlinear vehicle dynamics. The objective of this paper is to propose a state estimation method using unscented Kalman filter for nonlinear vehicle dynamics. The effectiveness of the proposed method is verified by numerical simulations.Keywords: State estimation, control systems, observer systems, unscented Kalman filter, nonlinear vehicle dynamics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5362603 Material Properties Evolution Affecting Demisability for Space Debris Mitigation
Authors: Chetan Mahawar, Sarath Chandran, Sridhar Panigrahi, V. P. Shaji
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The ever-growing advancement in space exploration has led to an alarming concern for space debris removal as it restricts further launch operations and adventurous space missions; hence various technologies and methods are explored for re-entry predictions and material selection processes for mitigating space debris. The selection of material and operating conditions is determined with the objective of lightweight structure and ability to demise faster subject to spacecraft survivability during its mission. The various evolving thermal material properties such as emissivity, specific heat capacity, thermal conductivity, radiation intensity, etc. affect demisability of spacecraft. Thus, this paper presents the analysis of evolving thermal material properties of spacecraft, which affect the demisability process and thus estimate demise time using the demisability model by incorporating evolving thermal properties for sensible heating followed by the complete or partial break-up of spacecraft. The demisability analysis thus concludes that the best suitable spacecraft material is based on the least estimated demise time, which fulfills the criteria of design-for-survivability and as well as of design-for-demisability.
Keywords: Demisability, emissivity, lightweight, re-entry, survivability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2572602 Enhancement of Heat Transfer Rate in a Solar Flat Plate Collector Using Twisted Tapes and Wire Coiled Turbulators
Authors: S. Vijayakumar, R. Vinoth, K. Abilash, P. Praveen
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Effects of insertion of coiled wire in juxtaposition with twisted tapes on heat transfer rate and solar radiation without disturbing the flow inside the riser tubes in a solar flat plate collector is experimentally reconnoitered in this present work. The wire coil used as a turbulator is placed inside the riser tube while the twisted tape is inserted into the wire coil to create a continuous swirling flow along the tube wall. The results of the heat transfer have been compared well with the available results. The heat transfer rate in the collector has been found to be increased by 18% to 70%. Solar water heaters having inserts in the flow tubes perform better than the conventional plain ones. It has been observed that heat losses are reduced consequently increasing the thermal performance about 30% over the plain water heaters under the same operating conditions. The effect of twisted tape with wire coils, flow Reynolds number, and the intensity of solar radiation on the thermal performance of the solar water heater has been presented. Effects of insertion of coiled wire in juxtaposition with twisted tapes on heat transfer rate and solar radiation without disturbing the flow inside the riser tubes in a solar flat plate collector is experimentally reconnoitered in this present work. The wire coil used as a turbulator is placed inside the riser tube while the twisted tape is inserted into the wire coil to create a continuous swirling flow along the tube wall. The results of the heat transfer have been compared well with the available results. The heat transfer rate in the collector has been found to be increased by 18% to 70%. Solar water heaters having inserts in the flow tubes perform better than the conventional plain ones. It has been observed that heat losses are reduced consequently increasing the thermal performance about 30% over the plain water heaters under the same operating conditions. The effect of twisted tape with wire coils, flow Reynolds number, and the intensity of solar radiation on the thermal performance of the solar water heater has been presented.
Keywords: Solar Flat Plate Collector, Heat Transfer, Twisted tape, Wire coiled turbulators
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28282601 Contribution to the Study of Thermal Conductivity of Porous Silicon Used In Thermal Sensors
Authors: A. Ould-Abbas, M. Bouchaour, , M. Madani, D. Trari, O. Zeggai, M. Boukais, N.-E.Chabane-Sari
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The porous silicon (PS), formed from the anodization of a p+ type substrate silicon, consists of a network organized in a pseudo-column as structure of multiple side ramifications. Structural micro-topology can be interpreted as the fraction of the interconnected solid phase contributing to thermal transport. The reduction of dimensions of silicon of each nanocristallite during the oxidation induced a reduction in thermal conductivity. Integration of thermal sensors in the Microsystems silicon requires an effective insulation of the sensor element. Indeed, the low thermal conductivity of PS consists in a very promising way in the fabrication of integrated thermal Microsystems.In this work we are interesting in the measurements of thermal conductivity (on the surface and in depth) of PS by the micro-Raman spectroscopy. The thermal conductivity is studied according to the parameters of anodization (initial doping and current density. We also, determine porosity of samples by spectroellipsometry.Keywords: micro-Raman spectroscopy, mono-crysatl silicon, porous silicon, thermal conductivity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18472600 Analytical Based Truncation Principle of Higher-Order Solution for a x1/3 Force Nonlinear Oscillator
Authors: Md. Alal Hosen
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In this paper, a modified harmonic balance method based an analytical technique has been developed to determine higher-order approximate periodic solutions of a conservative nonlinear oscillator for which the elastic force term is proportional to x1/3. Usually, a set of nonlinear algebraic equations is solved in this method. However, analytical solutions of these algebraic equations are not always possible, especially in the case of a large oscillation. In this article, different parameters of the same nonlinear problems are found, for which the power series produces desired results even for the large oscillation. We find a modified harmonic balance method works very well for the whole range of initial amplitudes, and the excellent agreement of the approximate frequencies and periodic solutions with the exact ones has been demonstrated and discussed. Besides these, a suitable truncation formula is found in which the solution measures better results than existing solutions. The method is mainly illustrated by the x1/3 force nonlinear oscillator but it is also useful for many other nonlinear problems.
Keywords: Approximate solutions, Harmonic balance method, Nonlinear oscillator, Perturbation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13832599 Simulation of Propagation of Cos-Gaussian Beam in Strongly Nonlocal Nonlinear Media Using Paraxial Group Transformation
Authors: A. Keshavarz, Z. Roosta
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In this paper, propagation of cos-Gaussian beam in strongly nonlocal nonlinear media has been stimulated by using paraxial group transformation. At first, cos-Gaussian beam, nonlocal nonlinear media, critical power, transfer matrix, and paraxial group transformation are introduced. Then, the propagation of the cos-Gaussian beam in strongly nonlocal nonlinear media is simulated. Results show that beam propagation has periodic structure during self-focusing effect in this case. However, this simple method can be used for investigation of propagation of kinds of beams in ABCD optical media.
Keywords: Paraxial group transformation, nonlocal nonlinear media, Cos-Gaussian beam, ABCD law.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8002598 Nonlinear Solitary Structures of Electron Plasma Waves in a Finite Temperature Quantum Plasma
Authors: Swarniv Chandra, Basudev Ghosh
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Nonlinear solitary structures of electron plasma waves have been investigated by using nonlinear quantum fluid equations for electrons with an arbitrary temperature. It is shown that the electron degeneracy parameter has significant effects on the linear and nonlinear properties of electron plasma waves. Depending on its value both compressive and rarefactive solitons can be excited in the model plasma under consideration.Keywords: Electron Plasma Waves, Finite Temperature Model, Modulational Instability, Quantum Plasma, Solitary structure
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16752597 Novel Design and Analysis of a Brake Rotor
Authors: Sharath Kumar T., S.Vinodh
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Over the course of the past century, the global automotive industry-s stance towards safety has evolved from one of contempt to one nearing reverence. A suspension system that provides safe handling and cornering capabilities can, with the help of an efficient braking system, improve safety to a large extent. The aim of this research is to propose a new automotive brake rotor design and to compare it with automotive vented disk rotor. Static structural and transient thermal analysis have been carried out on the vented disk rotor and proposed rotor designs to evaluate and compare their performance. Finite element analysis was employed for both static structural and transient thermal analysis. Structural analysis was carried out to study the stress and deformation pattern of the rotors under extreme loads. Time varying temperature load was applied on the rotors and the temperature distribution was analysed considering cooling parameters (convection and radiation). This dissertation illustrates the use of Finite Element Methods to examine models, concluding with a comparative study of the proposed rotor design and the conventional vented disk rotor for structural stability and thermal efficiency.Keywords: Disk brakes, CAD model, rotor design, structural and thermal analysis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32502596 Automatic Iterative Methods for the Multivariate Solution of Nonlinear Algebraic Equations
Authors: Rafat Alshorman, Safwan Al-Shara', I. Obeidat
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Most real world systems express themselves formally as a set of nonlinear algebraic equations. As applications grow, the size and complexity of these equations also increase. In this work, we highlight the key concepts in using the homotopy analysis method as a methodology used to construct efficient iteration formulas for nonlinear equations solving. The proposed method is experimentally characterized according to a set of determined parameters which affect the systems. The experimental results show the potential and limitations of the new method and imply directions for future work.Keywords: Nonlinear Algebraic Equations, Iterative Methods, Homotopy Analysis Method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18692595 On the Strong Solutions of the Nonlinear Viscous Rotating Stratified Fluid
Authors: A. Giniatoulline
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A nonlinear model of the mathematical fluid dynamics which describes the motion of an incompressible viscous rotating fluid in a homogeneous gravitational field is considered. The model is a generalization of the known Navier-Stokes system with the addition of the Coriolis parameter and the equations for changeable density. An explicit algorithm for the solution is constructed, and the proof of the existence and uniqueness theorems for the strong solution of the nonlinear problem is given. For the linear case, the localization and the structure of the spectrum of inner waves are also investigated.Keywords: Galerkin method, Navier-Stokes equations, nonlinear partial differential equations, Sobolev spaces, stratified fluid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13872594 Comparative Finite Element Simulation of Nonlinear Vibrations and Sensor Output Voltage of Smart Piezolaminated Structures
Authors: Ruediger Schmidt, Thang Duy Vu
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Two geometrically nonlinear plate theories, based either on first- or third-order transverse shear deformation theory are used for finite element modeling and simulation of the transient response of smart structures incorporating piezoelectric layers. In particular the time histories of nonlinear vibrations and sensor voltage output of a thin beam with a piezoelectric patch bonded to the surface due to an applied step force are studied.
Keywords: Nonlinear vibrations, piezoelectric patches, sensor voltage output, smart structures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19542593 Workplace Monitoring During Interventional Cardiology Procedures
Authors: N. Todorovic, I. Bikit, J. Nikolov, S. Forkapic, D. Mrdja, S. Todorovic
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Interventional cardiologists are at greater risk from radiation exposure as a result of the procedures they undertake than most other medical specialists. A study was performed to evaluate operator dose during interventional cardiology procedures and to establish methods of operator dose reduction with a radiation protective device. Different procedure technique and use of protective tools can explain big difference in the annual equivalent dose received by the professionals. Strategies to prevent and monitor radiation exposure, advanced protective shielding and effective radiation monitoring methods should be applied.Keywords: absorbed dose rate measurements, annualequivalent dose, protective device.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14872592 Performance of Single Pass Down Stream Solar Air Collector with Inclined Multiple V-Ribs
Authors: Manivannan A, Velmurugan M
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Solar air heater is a type of heat exchanger which transforms solar radiation into heat energy. The thermal performance of conventional solar air heater has been found to be poor because of the low convective heat transfer coefficient from the absorber plate to the air. It is attributed to the formation of a very thin boundary layer at the absorber plate surface commonly known as viscous sub-layer. Thermal efficiency of solar air heater can be improved by providing the artificial roughness on absorber plate is the most efficient technique. In this paper an attempt is made to provide artificial roughness by incorporating inclined multiple V-ribs in the underside of the absorber plate. 60˚V – ribs are arranged inclined to the direction of air flow. Performance of collector estimated theoretically and experimentally. Results of the investigation reveal that thermal efficiency of collector with multiple V-ribs increased by 14%.
Keywords: Artificial roughness, inclined multiple V-ribs, performance, Solar air collector.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25602591 Modeling and Numerical Simulation of Sound Radiation by the Boundary Element Method
Authors: Costa, E.S., Borges, E.N.M., Afonso, M.M.
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The modeling of sound radiation is of fundamental importance for understanding the propagation of acoustic waves and, consequently, develop mechanisms for reducing acoustic noise. The propagation of acoustic waves, are involved in various phenomena such as radiation, absorption, transmission and reflection. The radiation is studied through the linear equation of the acoustic wave that is obtained through the equation for the Conservation of Momentum, equation of State and Continuity. From these equations, is the Helmholtz differential equation that describes the problem of acoustic radiation. In this paper we obtained the solution of the Helmholtz differential equation for an infinite cylinder in a pulsating through free and homogeneous. The analytical solution is implemented and the results are compared with the literature. A numerical formulation for this problem is obtained using the Boundary Element Method (BEM). This method has great power for solving certain acoustical problems in open field, compared to differential methods. BEM reduces the size of the problem, thereby simplifying the input data to be worked and reducing the computational time used.
Keywords: Acoustic radiation, boundary element
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14262590 Quasilinearization–Barycentric Approach for Numerical Investigation of the Boundary Value Fin Problem
Authors: Alireza Rezaei, Fatemeh Baharifard, Kourosh Parand
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In this paper we improve the quasilinearization method by barycentric Lagrange interpolation because of its numerical stability and computation speed to achieve a stable semi analytical solution. Then we applied the improved method for solving the Fin problem which is a nonlinear equation that occurs in the heat transferring. In the quasilinearization approach the nonlinear differential equation is treated by approximating the nonlinear terms by a sequence of linear expressions. The modified QLM is iterative but not perturbative and gives stable semi analytical solutions to nonlinear problems without depending on the existence of a smallness parameter. Comparison with some numerical solutions shows that the present solution is applicable.
Keywords: Quasilinearization method, Barycentric lagrange interpolation, nonlinear ODE, fin problem, heat transfer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18282589 The Comparison of Finite Difference Methods for Radiation Diffusion Equations
Authors: Ren Jian, Yang Shulin
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In this paper, the difference between the Alternating Direction Method (ADM) and the Non-Splitting Method (NSM) is investigated, while both methods applied to the simulations for 2-D multimaterial radiation diffusion issues. Although the ADM have the same accuracy orders with the NSM on the uniform meshes, the accuracy of ADM will decrease on the distorted meshes or the boundary of domain. Numerical experiments are carried out to confirm the theoretical predication.Keywords: Alternating Direction Method, Non-SplittingMethod, Radiation Diffusion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13892588 Internal Surface Measurement of Nanoparticle with Polarization-interferometric Nonlinear Confocal Microscope
Authors: Chikara Egami, Kazuhiro Kuwahara
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Polarization-interferometric nonlinear confocal microscopy is proposed for measuring a nano-sized particle with optical anisotropy. The anisotropy in the particle was spectroscopically imaged through a three-dimensional distribution of third-order nonlinear dielectric polarization photoinduced.Keywords: nanoparticle, optical storage, microscope
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13152587 Parameter Estimation using Maximum Likelihood Method from Flight Data at High Angles of Attack
Authors: Rakesh Kumar, A. K. Ghosh
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The paper presents the modeling of nonlinear longitudinal aerodynamics using flight data of Hansa-3 aircraft at high angles of attack near stall. The Kirchhoff-s quasi-steady stall model has been used to incorporate nonlinear aerodynamic effects in the aerodynamic model used to estimate the parameters, thereby, making the aerodynamic model nonlinear. The Maximum Likelihood method has been applied to the flight data (at high angles of attack) for the estimation of parameters (aerodynamic and stall characteristics) using the nonlinear aerodynamic model. To improve the accuracy level of the estimates, an approach of fixing the strong parameters has also been presented.Keywords: Maximum Likelihood, nonlinear, parameters, stall.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21702586 Simulation of Hamming Coding and Decoding for Microcontroller Radiation Hardening
Authors: Rehab I. Abdul Rahman, Mazhar B. Tayel
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This paper presents a method of hardening the 8051 micro-controller, able to assure reliable operation in the presence of bit flips caused by radiation. Aiming at avoiding such faults in the 8051 micro-controller, Hamming code protection was used in its SRAM memory and registers. A VHDL code has been used for this hamming code protection.
Keywords: Radiation, hardening, bitflip, hamming code.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29432585 Radiation Effect on Unsteady MHD Flow over a Stretching Surface
Authors: Zanariah Mohd Yusof, Siti Khuzaimah Soid, Ahmad Sukri Abd Aziz, Seripah Awang Kechil
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Unsteady magnetohydrodynamics (MHD) boundary layer flow and heat transfer over a continuously stretching surface in the presence of radiation is examined. By similarity transformation, the governing partial differential equations are transformed to a set of ordinary differential equations. Numerical solutions are obtained by employing the Runge-Kutta-Fehlberg method scheme with shooting technique in Maple software environment. The effects of unsteadiness parameter, radiation parameter, magnetic parameter and Prandtl number on the heat transfer characteristics are obtained and discussed. It is found that the heat transfer rate at the surface increases as the Prandtl number and unsteadiness parameter increase but decreases with magnetic and radiation parameter.Keywords: Heat transfer, magnetohydrodynamics, radiation, unsteadiness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2625