• Proceedings of the KSME Conference
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• 2003.11a
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• pp.290-295
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• 2003

Among the thermal analysis methods for Multi-Layer Insulation(MLI), effective emittance, diffusion MLI node and arithmetic MLI node methods are compared. The methods have been applied to the aluminum panel under the low earth orbit environment. TRASYS program is used for geometrical math modeling and SINDA program for thermal math modeling and temperature calculation. Test cases are selected according to MLI area on the panel. Temperature results are calculated and compared under the ratio of absorptivity and emissivity.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.37-37
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• 2000

This paper introduces the Performance Monitoring System(PMS) in a thermal power plant. The purpose of the PMS is to offer the operator current performance information of plant which could be an index of plant status or information to improve plant efficiency. The PMS of Bukcheju thermal power plant unit ＃2&3 is implemented under the SIEMENS DCS which supplies about 150 function blocks for performance calculation and all measured signals. The performance of unit, boiler, turbines, feedwater heaters, condenser, airpreheaters, feedwater pumps will be monitored and updated for every 5 minutes in PMS of Bukcheju TPP.

• Proceedings of the KWS Conference
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• 2005.11a
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• pp.126-128
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• 2005

This paper presents a 3-D finite element analysis of a magneto-thermal coupled problem with moving conductor. In the magnetic and thermal analyses, temperature-dependent magnetic and thermal material properties were considered. Transient finite element method for analysis of moving conductor needs many number of elements and much time to make calculation. Therefore, in this paper, finite element formulation derived from quasi-state is adopted. Finite element results were compared with the experimental results. The results demonstrate that this approach is suitable to solve the magneto-thermal coupled problem.

• Bulletin of the Society of Naval Architects of Korea
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• v.10 no.1
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• pp.15-20
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• 1973

In this paper, it is desired to show a simplified analytical method in estimating the thermal stresses in the heat affected zone of butt welded joint. A finite strip as shown in Fig.1 is taken as a analytical model for stress analysis. Expressing the temperature distributions by Fourier series, the thermal stresses are obtained. From the numerical sample calculation, the following results can be obtained. (1) Thermal stresses can be estimated by the sujected method. (2) The stress component, which is parallel to the weld direction is the largest stress component in major part of the strip. (3) In obtaining a stress component for the engineering purpose, length of the strip can be treated as five times of the thickness with same degree of convergency.

• Nuclear Engineering and Technology
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• v.52 no.11
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• pp.2620-2629
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• 2020

As an early stage in the development of a water calorimeter, this study established a computer simulation methodology for analyzing the thermal behavior of a water calorimeter based on radiation transport and energy deposition. As a result, this study developed a method wherein the energy deposition distribution, which is obtained by applying Monte Carlo methods in water calorimeters, is directly used as a heat source for the thermal analysis model. Based on the proposed method, heat transfer in a water vessel and the effect of thermistor self-heating were analyzed. Through an analysis of the water velocities with and without a water vessel, it was found that a water vessel can serve as a convection barrier. Furthermore, it was confirmed that when considering thermistor self-heating, the water temperature change at the thermistor location is 0.219 mK higher compared to that when the thermistor was not considered. Therefore, thermistor self-heating must be considered to analyze the thermal behavior of a water calorimeter more accurately.

• Korean Journal of Optics and Photonics
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• v.10 no.3
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• pp.237-242
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• 1999

Taking into consideration the thermal lensing effects of laser rods, depolarization losses of laser beams induced by the thermal birefringence were calculated. The numerical model proposed for the calculation, which is based on the paraxial ray optics formulation and provides explicit expressions of optical path lengths for various optical elements, was described in detail. Calculated results were compared with those of Jones matrix formulation and experiments. The calculated results are in good agreement with experimental results.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.267-275
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• 1998

In this study, the instantaneous heat flux measurement probe and the linkage system for the measurement of the instantaneous temperature and heat flux of the DI mono cylinder diesel engine were developed, and these were proved to have a good reliability and sensibility. A 3-D FEM model which consist of full piston to accommodate the eccentric bowl in the piston head, was applied for the analysis of the thermal stress and the temperature distribution. The mean heat flux on the piston head was used as boundary condition for the analysis of piston. The analysis showed that thermal stress concentrate on the bowl and inner surface of pin hall.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.507-514
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• 2012

In the present research, NASA LRB plume radiation models are reconstructed with Thermal Desktop software, where the radiation to vehicle base environment can be calculated. The calculation shows the similar radiation heat compared to NASA prediction. Based on LRB plume radiation model, a KSLV-II thermal radiation model is proposed.

• Journal of the Korean Solar Energy Society
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• v.28 no.4
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• pp.43-49
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• 2008

The purpose of this study is to present the simulation results and an overview of the performance assessment of a solar heating & cooling system by means of the $200m^2$ evacuated tube solar collector. The simulation was carried out using the thermal simulation code TRNSYS with new model of a single-effect LiBr/$H_{2}O$ absorption chiller developed by this study. The calculation was performed for yearly long-term thermal performance and for two design factors: the solar hot water storage tank and the cold water storage tank. As a result, it was anticipated that the yearly mean system efficiency is 46.7% and the solar fraction for the heating, cooling and hot water supply are about 84.4 %, 41.7% and 72.4%, respectively.

• Journal of Energy Engineering
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• v.8 no.2
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• pp.224-232
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• 1999

Latent heat storage system using micro-encapsuled phase change material is effective method for floor heating of house and building. The temperature profile in capsule block and flow rate of hot water are important parameters for the development of heat storage system. In the present study, a mathematical model based on 3-D, non-steady state, Navier-Stokes equations, scalar conservation equations and turbulence model ($\kappa$-$\varepsilon$), is used to predict the temperature profiles in capsule and the velocity vectors in hot water pipe. The multi-block grids and fine grids embedding are used to join the circle in hot water pipe and square in capsule block. The phase change process of the capsule is quite complex not only because the size of phase change material is very small, but also because phase change material is mixed with the cement to form thermal storage block. In calculation, it's assumed that the phenomena of phase change is limited only the thermal properties of phase change material and the change of boundary is not happened in capsule. The purpose of this study is to calculate the temperature profiles in capsule block and velocity vectors in hot water pipe using the numerical calculation. Two kinds of thermal boundary condition were considered, the first (case 1) is the adiabatic condition for the both outside surfaces of the wall, the second (case 2) is the case in which one surface is natural convection with atmosphere and another surface is adaibatic. Calculation results are shown that the temperature profile in capsule block for case 1 is higher than that for case 2 due to less heat loss in adaibatic surface. Specially, in the domain of near Y=0, the difference of temperature is greater in case 1 than in case 2. The detailed experimental data of capsule block on the temperature profile and the thermal properties such as specific heat and coefficient of heat transfer with the various temperature are required to predict more exact phenomena of heat transfer.