• Title/Summary/Keyword: Two-dimensional temperature distribution

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A New Model for the Analysis of Non-spherical Particle Growth Using the Sectional Method (구간해석방법을 통한 새로운 비구형 입자성장해석 모델)

  • Jeong, Jae-In;Choi, Man-Soo
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.416-421
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    • 2000
  • We have developed a simple model for describing the non-spherical particle growth phenomena using modified 1-dimensional sectional method. In this model, we solve simultaneously particle volume and surface area conservation sectional equations which consider particles' irregularities. From the correlation between two conserved properties of sections, we can predict the evolution of the aggregates' morphology. We compared this model with a simple monodisperse-assumed model and more rigorous two dimensional sectional model. For the comparison, we simulated silica and titania particle formation and growth in a constant temperature reactor environment. This new model shows a good agreement with the detailed two dimensional sectional model in total number concentration, primary particle size. The present model can also successfully predict particle size distribution and morphology without costing very heavy computation load and memory needed for the analysis of two dimensional aerosol dynamics.

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Heat Transfer Analysis of Friction Welding of A2024 to SM45C (A2024 와 SM45C 마찰용접의 열전달 해석)

  • 이상윤;윤병수
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.10 no.1
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    • pp.65-70
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    • 2001
  • The hear transfer mechanism initiating the friction welding is examined and a transient three dimensional heat conduc-tion model for the welding of two dissimilar cylindrical metal bars is investigated. The cylindrical metal bars are made of materials made of A2024 and SM 45C. Numerical simulations of heat flow are performed using the finite volume method. Respectively. Commercial FLUENT code is used in the heat flow simulation and maximum temperature and distribution of temperature are calculated. Temperature of friction welded joining face is compared with the temperature distribution measured by experiment and numerical simulation. The maximum temperature of friction welded joining face is lower than melting point of A2024-T6 aluminum alloy using insert metal. The temperature distribution of friction welded join- ing face with insert metal is more uniform than that of without inset metal.

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A Numerical Study on Temperature Distribution on Ceiling for Different Locations and Sizes of the Outflow Opening (유출개구부의 위치와 크기에 따른 천장의 온도분포에 관한 수치연구)

  • 박외철;김재일
    • Journal of the Korean Society of Safety
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    • v.16 no.2
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    • pp.7-12
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    • 2001
  • The finite volume method was utilized for computation of convection heat transfer in a two-dimensional enclosure with an inflow opening and an outflow opening. The objective of this study is to investigate temperature distribution on ceiling for different locations and sizes of the outflow opening. The inflow opening was set to be H$_{i}$=0 and U=50. The results fur different sizes of the opening H$_{0}$=0.1, 0.2, 0.3, and 0.4 shooed similar flow patterns and temperature distribution. Location of the outflow opening, however, influenced significantly on the temperature distribution on the ceiling.ing.

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Temperature Analysis of the Cylindrical Structure with Multi-Holes of HANARO Irradiation Test (하나로 조사시험용 다공 원통헝 구조물의 온도해석)

  • Choi Young-Jin;Kang Young-Hwan;Lee Young-Shin
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.17 no.4
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    • pp.405-412
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    • 2004
  • During the irradiation tests of material and fuel rod, all components of the cylindrical structure with multiple holes act like heat sources due to high gamma heat and fission heat. The objective of this study is to formulate the general solution for the temperature distribution to estimate the thermal integrity of structure during irradiation tests. For the temperature distribution analysis, the two-dimensional heat conduction theory is used. The unmerical analysis is performed by the commercial finite element analysis code, ANSYS 6.1. If the cylindrical structure with hole number would not exceed three holes, the analysis results and finite element results are good agreement together. For the structure with four holes, the discrepancy between FE results and analysis results of the structural temperature distribution is increased.

Dynamic analysis of a functionally graded tapered rotating shaft under thermal load via differential quadrature finite elements method

  • Fethi, Hadjoui;Ahmed, Saimi;Ismail, Bensaid;Abdelhamid, Hadjoui
    • Advances in aircraft and spacecraft science
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    • v.10 no.1
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    • pp.19-49
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    • 2023
  • The present study proposes a theoretical and numerical investigation on the dynamic response behaviour of a functional graded (FG) ceramic-metal tapered rotor shaft system, by the differential quadrature finite elements method (DQFEM) to identify the natural frequencies for modelling and analysis of the structure with suitable validations. The purpose of this paper is to explore the influence of heat gradients on the natural frequency of rotation of FG shafts via three-dimensional solid elements, as well as a theoretical examination using the Timoshenko beam mode, which took into account the gyroscopic effect and rotational inertia. The functionally graded material's distribution is described by two distribution laws: the power law and the exponential law. To simulate varied thermal conditions, radial temperature distributions are obtained using the nonlinear temperature distribution (NLTD) and exponential temperature distribution (ETD) approaches. This work deals with the results of the effect on the fundamental frequencies of different material's laws gradation and temperature gradients distributions. Attempts are conducted to identify adequate explanations for the behaviours based on material characteristics. The effect of taper angle and material distribution on the dynamic behaviour of the FG conical rotor system is discussed.

A Study on In-Cylinder Measurement of Flame Temperature and Soot Distribution in D.I. Diesel Engine Using Tow-Color Method (이색법을 이용한 직접 분사식 디젤엔진 실린더내의 화염 분도 및 Soot 분포 측정에 관한 연구)

  • 박정규;정수훈;원영호
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.7
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    • pp.42-53
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    • 1999
  • Two dimensional flame temperature and KL value distribution from the luminous flame containing soot in a DI diesel engine were measured by the tow-color method using tow different wavelengths of the flame image. The combustion chamber of a DI diesel engine was visualized by elongating the piston and cylinder and the flame in the combustion chamber was photographed on a nega-color film using a high speed camera. In this study, color CCD camera was used to digitize the three color density of the film exposed to the flame and standard lamp . The accuracy of the measuring method depends on the calibration line of film made from a high temperature standard tungsten lamp. The formation and oxidization of soot in the diesel engine were studied by observing measured time history of KL factor and flame temperature . Also , effects of various shapes of combustion chamber and fuel injection on flame temperature. Also, effects of various shapes of combustion chamber and fuel injection on flame temperature and KL value distribution were examined.

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A two dimensional analysis of the evolution of the particle size distribution in particle laden high temperature jet flows including the effects of coagulation and buoyancy (입자가 부유된 고온의 제트유동에서 응집과 부력을 고려한 이차원 입자크기 분포해석)

  • Lee, Bang-Won;Choe, Man-Su;Hwang, Jeong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.3
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    • pp.380-391
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    • 1997
  • A numerical study has been done on the evolution of particle size distribution in particle laden high temperature jet flows undergoing convection, diffusion, thermophoresis and coagulation. The dynamic behavior of these particles have been modelled by approximating the particle size distribution by a lognormal function throughout the process and the moments of the particle size distribution have been used to solve the general dynamic equation. The size distributions of spherical particles in the radial and axial direction have been obtained including the effect of buoyancy. Of particular interests are the variations of geometric mean diameter, number concentration and polydispersity. Results show that buoyancy significantly alters the size distribution in both axial and radial direction. One dimensional analysis for non-spherical particles has also been done and the results have been compared with the existing experimental data.

Application of Commercial FEM Code to Coupled Analysis of Casting Deformation (범용 구조해석 프로그램의 주물 열변형 해석에의 적용성)

  • Kim, Ki-Young;Kim, Jung-Tae;Choi, Jung-Gil
    • Journal of Korea Foundry Society
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    • v.22 no.4
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    • pp.192-199
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    • 2002
  • Dimensional defects of castings are mainly due to the stresses and strains caused by a nonuniform temperature distribution and phase transformation during solidification and cooling, and by mechanical constraint between the mold and casting. It is, however, nearly impossible to trace movements of the casting and mold during solidification and cooling by experimental measurements for castings with complex shape. Two and three dimensional deformation analyses of the casting and the mold were performed using commercial finite element code, MARC. It was possible to calculate deformation and temperature distribution in the casting and mold simultaneously. Cooling curves of the casting obtained by calculation were close to that measured in the field since it was possible to treat latent heat evolution of the casting which could be divided into two parts, primary and eutectic parts. Mold bent inward just after pouring due to the temperature gradient across the mold thickness, and mold returned to its previous position with time. Plastic deformation occurred at the part of the casting where solidification was slow.

Measurement using Low-temperature Scanning Hall Probe Microscopy and Analysis of Local Current Distribution using Inversion Problem Technique (저온 주사 홀소자 현미경과 역변환 방법을 이용한 국소적 전류 분포 분석)

  • Cho, B.R.;Park, S.K.;Park, H.Y.;Ri, H.C.
    • Progress in Superconductivity
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    • v.13 no.1
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    • pp.34-39
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    • 2011
  • We have performed measurements of the local magnetic field distribution of YBCO coated conductors using Low-temperature Scanning Hall Probe Microscopy (LT-SHPM). Distribution of stray magnetic field of various types of YBCO coated conductors in the superconducting state was measured in presence of external magnetic fields. We analyzed one dimensional and two dimensional local current distribution using inversion technique from the magnetic field distribution.

A Study on the Temperature Distribution of Metal Casting Mould (주조금형(鑄造金型)의 온도분포(溫度分布)에 관한 연구(硏究))

  • Min, Soo-Hong;Kim, Ok-Sam;Koo, Bon-Kwan
    • Journal of Korea Foundry Society
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    • v.11 no.1
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    • pp.79-84
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    • 1991
  • The process of solidification of metal is accompanied by liquid-solid change and known as Stefan's heat conduction problem on the moving boundary. In this study the temperature distribution in ingot and metallic mould during casting was analyzed by the two dimensional heat conduction theory. The transient temperature distribution was numerically calculated using a finite element method on the nodal point of mesh screen representing ingot and mould cross section. The theory was applied on the casting of aluminum(purity ; 99%) in flat ingot mould of GC25. The analysis will make it possible to calculate an optimum mould shape of which temperature gradient becomes minimum.

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