• Title/Summary/Keyword: Thermal Parameter

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Design of a Compensation Algorithm for Thermal Infrared Data considering Environmental Temperature Variations (주변 환경 온도 변화를 고려한 열화상 온도 데이터의 보정 알고리즘 설계)

  • Song, Seong-Ho
    • Journal of IKEEE
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    • v.25 no.2
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    • pp.261-266
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    • 2021
  • This paper suggests design methodology for thermal infrared data correction algorithms considering environmental temperature variations. First, a thermal infrared measurement model is suggested by a parameter-dependent first-order input-output equation using the relationship between infrared measurement data and model environmental parameters. In order to compensate the influence of environmental temperatures on infrared data, a compensation function is identified. Through experiments, the proposed algorithm is shown to reduce the influence of environmental temperatures on the infrared data effectively.

Modeling and Parameter Estimation of Superheater and Desuperheater (과열기와 과열저감기에 대한 모델링 및 파라미터 추정)

  • Lee, Soon-Young;Shin, Hwi-Beom
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.11
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    • pp.2012-2015
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    • 2010
  • In this paper, the mathematical models of the superheater and the desuperheater are derived based on the fundamental laws of physics, mass and energy balance. The parameters of the models are developed for the 500[MW] thermal power plant using the actual data. The simulated model outputs are well matched with the actual ones. It is expected that the proposed models are useful for the temperature controller design of the thermal power plant.

Thermal Transient Analysis of Electric Initiator Used SUS 304 Bridgewire (SUS 304 발열선을 사용한 전기식 착화기의 열특성 분석)

  • Yoon Ki-Eun;Ryu Byung-Tae;Choi Hong-Seok
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2005.11a
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    • pp.184-187
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    • 2005
  • Performing thermal transient test on electric initiator with SUS 304 bridgewire(diameter 2.3mil) and $Zr-KClO_4$ primary charge and analysing the test data using Fitted Wire Model shows that the thermal characteristic parameter related to primary charge is changed sharply around $300^{\circ}C$. It is determined that this phenomenon is due to endothermic reaction from phase transition of $KClO_4$, which is used as primary charge, and to physical change of thermal transient interface between bridgewire and primary charge. With this results, useful temperature range for the parameter obtained from thermal transient test can be suggested.

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A Study of Borehole Thermal Behavior with 1-Dimensional Model;Field Test Analysis included (1차원 모델에 의한 보어홀 열거동 해석 및 현지측정)

  • Kim, Dae-Ki;Woo, Joung-Son;Ro, Jeong-Geun;Lee, Se-Kyoun
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.550-554
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    • 2007
  • A one-dimensional heat transfer model coupled with parameter estimation is developed in this study to predict the effective thermal conductivities of soil formation and borehole resistances from in situ field test data. In this application a new method of using initial ignoring time(IIT) obtained from error estimation is tried and turned out to be successful in determining soil thermal conductivities. The validity of this model is accomplished through comparison of the predicted temperature profiles of the model with the data from laboratory scale experimental setting. Eleven test boreholes were constructed in Ochang, Chungcheong Buk Do, and thermal response test was carried out with each borehole. The results of the in situ tests were analyzed with our 1-D numerical model and compared with the results of line source method. The comparison shows that the thermal properties from line source method is a little lower (${\sim}95%$)than those from numerical method. The reason of such result seems to be the lower thermal conductivity of grout material, which is not counted in line source method.

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A nonlocal integral Timoshenko beam model for free vibration analysis of SWCNTs under thermal environment

  • Liani, Mohamed;Moulay, Noureddine;Bourada, Fouad;Addou, Farouk Yahia;Bourada, Mohamed;Tounsi, Abdelouahed;Hussain, Muzamal
    • Advances in materials Research
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    • v.11 no.1
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    • pp.1-22
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    • 2022
  • In this paper, the nonlocal integral Timoshenko beam model is employed to study the free vibration characteristics of singled walled carbon nanotubes (SWCNTs) including the thermal effect. Based on the nonlocal continuum theory, the governing equations of motion are formulated by considering thermal effect. The influences of small scale parameter, the chirality of SWCNTs, the vibrational mode number, the aspect ratio of SWCNTs and temperature changes on the thermal vibration properties of single-walled nanotubes are examined and discussed. Results indicate significant dependence of natural frequencies on the nonlocal parameter, the temperature change, the aspect ratio and the chirality of SWCNTs. This work should be useful reference for the application and the design of nanoelectronics and nanoelectromechanical devices that make use of the thermal vibration properties of SWCNTs.

Finite Element Analysis of Temperature Distribution and Thermally Caused Deformation in Ventilated Disk Brakes

  • Kim, Chung-Kyun
    • Tribology and Lubricants
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    • v.11 no.5
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    • pp.150-155
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    • 1995
  • In order to analyze the thermal effects of the rotor models, the finite element technique was used in this study. The length of the hat was investigated as a design parameter. At the start of each brake application the disk surface temperature rapidly increases to a maximum value and then decays due to external cooling and thermal conduction to the hat. The calculated results indicate that the long length of the hat shows the minimum deformation in axial direction, which is related to the thermal problems, coned wear, vibration and noise.

Edge wave propagation in an Electro-Magneto-Thermoelastic homogeneous plate subjected to stress

  • Kakar, Rajneesh;Kakar, Shikha
    • Structural Engineering and Mechanics
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    • v.53 no.6
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    • pp.1201-1214
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    • 2015
  • This paper introduces the combined effect of electric field, magnetic field and thermal field on edge wave propagating in a homogeneous isotropic prestressed plate of finite thickness and infinite length. The dispersion relation of edge wave has been obtained by using classical dynamical theory of thermoelasticity. The phase velocity has been computed and shown graphically for various initial stress parameter, electro-magneto parameter, electric parameter and thermoelastic coupling parameter.

Small-scale effects on wave propagation in curved nanobeams subjected to thermal loadings based on NSGT

  • Ibrahim Ghoytasi;Reza Naghdabadi
    • Advances in nano research
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    • v.16 no.2
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    • pp.187-200
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    • 2024
  • This study focuses on wave propagation analysis in the curved nanobeam exposed to different thermal loadings based on the Nonlocal Strain Gradient Theory (NSGT). Mechanical properties of the constitutive materials are assumed to be temperature-dependent and functionally graded. For modeling, the governing equations are derived using Hamilton's principle. Using the proposed model, the effects of small-scale, geometrical, and thermo-mechanical parameters on the dynamic behavior of the curved nanobeam are studied. A small-scale parameter, Z, is taken into account that collectively represents the strain gradient and the nonlocal parameters. When Z<1 or Z>1, the phase velocity decreases/increases, and the stiffness-softening/hardening phenomenon occurs in the curved nanobeam. Accordingly, the phase velocity depends more on the strain gradient parameter rather than the nonlocal parameter. As the arc angle increases, more variations in the phase velocity emerge in small wavenumbers. Furthermore, an increase of ∆T causes a decrease in the phase velocity, mostly in the case of uniform temperature rise rather than heat conduction. For verification, the results are compared with those available for the straight nanobeam in the previous studies. It is believed that the findings will be helpful for different applications of curved nanostructures used in nano-devices.

Study on Thermal Characteristics of IGBT (IGBT의 열 특성에 관한 연구)

  • Kang, Ey-Goo;Ahn, Byoung-Sub;Nam, Tae-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.70-70
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    • 2009
  • In this paper, we proposed 2500V Non punch-through(NPT) Insulated gate bipolar transistor(IGBT) for high voltage industry application. we carried out optimal simulation for high efficiency of 2500V NPT IGBT according to size of device. In results, we obtaind design parameter with 375um n-drift thickness, 15um gate length, and 8um emitter windows. After we simulate with optimal parameter, we obtained 2840V breakdown voltage and 3.4V Vce,sat. These design and process parameter will be used designing of more 2000V NPT IGBT devices.

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Modeling of a Building System and its Parameter Identification

  • Park, Herie;Martaj, Nadia;Ruellan, Marie;Bennacer, Rachid;Monmasson, Eric
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.975-983
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    • 2013
  • This study proposes a low order dynamic model of a building system in order to predict thermal behavior within a building and its energy consumption. The building system includes a thermally well-insulated room and an electric heater. It is modeled by a second order lumped RC thermal network based on the thermal-electrical analogy. In order to identify unknown parameters of the model, an experimental procedure is firstly detailed. Then, the different linear parametric models (ARMA, ARX, ARMAX, BJ, and OE models) are recalled. The parameters of the parametric models are obtained by the least square approach. The obtained parameters are interpreted to the parameters of the physically based model in accordance with their relationship. Afterwards, the obtained models are implemented in Matlab/Simulink(R) and are evaluated by the mean of the sum of absolute error (MAE) and the mean of the sum of square error (MSE) with the variable of indoor temperature of the room. Quantities of electrical energy and converted thermal energy are also compared. This study will permit a further study on Model Predictive Control adapting to the proposed model in order to reduce energy consumption of the building.