• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.115-118
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• 1991

The temperature distribution on the superconducting thin-film is analyzed as moving constant field is applied above upper critical field. The distribution of magnetic field is derived in the normal spot. Governing equation is obtained with the help of the equation of conservation of energy. The temperature distribution and the heat dissipation are obtained through computer simulation by the method of numerical analysis. Maximum temperature is occured in the most right side inside normal spot. The temperature is increased abruptly inside the normal spot, and decreased more gradually outside normal spot in the direction of moving field as velocity is increased. Increasing the velocity rather than increasing magnitude of the normal spot and the applied field makes maximum temperature larger. Heat dissipation is affected by the velocity rather than the magnitude of normal spot and the applied field.

• Journal of computational fluids engineering
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• v.7 no.2
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• pp.25-32
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• 2002

The velocity and temperature profiles in the cabin of the automobile affect greatly the comfortableness of passengers. In this paper, the three dimensional flow and temperature analysis in the cabin of real automobile have been peformed. The three dimensional Navier-Stokes equation solver was validated by comparing with the other numerical data of a 1/5 scale model. The temperature field of cavity was also analyzed for the validation of energy equation solver. After the code validation, the numerical analysis of real field of flow and temperature of an automobile was peformed and the present result provides the insight of flow and temperature field of the inside of cabin.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.1
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• pp.120-128
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• 1997

The variations of the temperature field in a passenger compartment were measured by using a HSI true color image processing system and TLC(Thermochromic Liquid Crystal) solution. This temperature measurement technique was proved to be useful for analyzing the ventilation flow. The flow field in the passenger compartment was visualized using a particle streak method with pulsed laser light sheet. The temperature field and flow field in the passenger copartment were affected significantly by the ventilation mode. The panel-vent mode heating had shorter elapse time to reach a uniform temperature than the foot-vent mode under the same ventilation condition and nonuniformity inside the passenger compartment could be minimized effectively by using the bilevel heating mode. The temperature increase rate in the rear passenger compartment was iower than the front compartment, especially in the vicinity of the rear seat occupants' knee level.

• Applied Science and Convergence Technology
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• v.27 no.1
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• pp.1-4
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• 2018

A sputtering-assisted magnetic field system was successfully developed for depositing crystalline Cu thin films at room temperature. This system employs a plasma source and an ion-beam gun with two magnetic field generators, which is covered with sputtering target and the ion-beam gun, simultaneously serving as sputtering plasma and a magnetic field generator. The formation of crystalline Cu thin films at room temperature was dominated by magnetic fields, which was revealed by preliminary experiments. This system can be employed for producing crystalline metal thin films at room temperature.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3532-3534
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• 2014

In theoretical simulations of proton transfer in DNA, environmental factors nearly have not been considered. In our calculations, using QM/MM method on the basis of CP2K, proton transfer on adenine-thymine base pair is studied in water, at wide scope temperature, and under the external electric field. Our results indicate that the external electric field induces the proton transfer at room temperature, and its intensity and temperature have some effect on hole localization and proton transfer.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1497-1500
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• 2006

The cooling effect of paddy fields was compared with those of other land-use areas (upland, urban park, and urban residential area) during midsummer. The temperature were monitored using data logger at one hour intervals in study sites. Diurnal temperature range of study areas in clear days was larger than in cloudy days. Also, diurnal temperature ranges in paddy field, upland, and park areas were larger than those in the urban residential area during clear days. The paddy field or upland area has shown more remarkable cooling effect compared to urban residential areas: Mean duration of temperature below $25^{\circ}C$ in the paddy field area is longer(7 to 8 hours) than in the residential area; The time to fall to below $25^{\circ}C$ in the paddy field area is sooner than in the residential area; Mean daily minimum temperature in the paddy field area is much lower than in the residential area.

• Computers and Concrete
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• v.26 no.4
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• pp.343-350
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• 2020

Concrete-filled steel tubular (CFST) members have been widely used in engineering, and their tube diameters have become larger and larger. But there is no research on the thermal field of large-diameter CFST structure. These studies focused on the thermal field of the large-diameter CFST structure under solar radiation. The environmental factors and the actual placement position were considered, and the finite element model (FEM) of the thermal field of CFST members under solar radiation (SR) was established. Then the FEM was verified by practical experiments. The most unfavorable temperature gradient model in the cross-section was proposed. The testing results showed that the temperature field of the large-diameter CFST member section was non-linearly distributed due to the influence of SR. The temperature field results of CFST members with different pipe diameters indicated that the larger the core concrete diameter was, the slower the central temperature changed, and there was a significant temperature difference between the center and the boundary. Based on the numerical model, the most unfavorable temperature gradient model in the section was proposed. The model showed that the temperature difference around the center of the circle is small, and the boundary temperature difference is significant. The maximum temperature difference is 15.22℃, which appeared in the southern boundary area of the specimen. Therefore, it is necessary to consider the influence of SR on the thermal field of the member for large-diameter CFST members in actual engineering, which causes a large temperature gradient in the member.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.3
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• pp.1114-1122
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• 1996

Variation of temperature field in a Hele-Shaw convection cell was measured by using a HSI true color image processing system and TLC(Thermochromic Liquid Crystal) solution. The relationship between the hue value of TLC color image and real temperature was obtained and this calibration result was used to measure the true temperature. The temperature field in the Hele-Shaw convection cell shows periodic characteristics of 45 sec at Ra = 9.3 * 10$\^$6/. The temperature field measurement technique developed in this study was proved to be a useful and powerful tool for analyzing the unsteady thermal fluid flows.

• Geomechanics and Engineering
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• v.12 no.3
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• pp.465-481
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• 2017

Thermal effect has great influence on wellbore stability in Dongfang 1-1 (DF 1-1) gas field, a reservoir with high-temperature and high-pressure. In order to analyze the wellbore stability in DF1-1 gas field, the variation of temperature field after drilling was analyzed. In addition, the effect of temperature changing on formation strength and the thermal expansion coefficients of formation were tested. On this basis, a wellbore stability model considering thermal effect was developed and the thermal effect on fracture pressure and collapse pressure was analyzed. One of the main challenges in this gas field is the decreasing temperature of the wellbore will reduce fracture pressure substantially, resulting in the drilling fluid leakage. If the drilling fluid density was reduced, kick or blowout may happen. Therefore, the key of safe drilling in DF1-1 gas field is to predict the fracture pressure accurately.

• Journal of Mechanical Science and Technology
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• v.14 no.8
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• pp.851-860
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• 2000

Temperature field and cooling rate are important parameters to influence the properties of clad layer and the heat affected zone. In this paper the temperature field and cooling rate of laser cladding are studied by a two-dimensional time-dependent finite element model. Experiment has been carried out by Nd:YAG laser cladding with wire feeding. Research results indicate that at the beginning of cladding, the width and depth of melt pool increase with cladding time. The cooling rate is related to position, cladding time, cladding speed, and preheating temperature. The temperature near melt pool changes rapidly while the temperature far from melt pool changes slowly. With the increase of cladding time, cooling rate decreases. The further the distance from the melt pool, the lower the temperature and the slower the cooling rate. The faster the cladding speed, the faster the cooling rate. The higher the preheating temperature, the slower the cooling rate. The FEM results coincide well with the experiment results.