• Title/Summary/Keyword: distribution of temperature

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An Experimental Study on the Lens Surface Temperature Distribution of P/C Headlamp Using the Three Category of H4 Halogen Bulbs (PIC 렌즈 전조등 렌즈면의 온도분포에 관한 실험적 연구)

  • 박경석;강병도
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.4
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    • pp.158-165
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    • 2002
  • This Paper deals with the headlamp lens surface temperature distribution of p/c headlamp using the three categories of H4 halogen bulbs. Glass is gradually replaced by P/C for the lens material off vehicle headlamp due to the weight reduction and stream lined body of a vehicle. With this trend, the newly established standards for a headlamp with a P/C lens in Europe requires that the heat generated by a bulb should not distort the lens surface. Also the requirements fur the bulb of a headlamp are being enforced in U.S.A & Europe. However, such requirements are not established yet in Korea. By using three kinds (60/55w, 100/90w, 130/90w) of H4 halogen bulbs in this experiment, the surface temperature distribution and Max. temperature on the lens were measured. The results of this study implies the necessity of requirement fur the bulb off headlamp.

Real Time Temperature Distribution Measurement of a Microheater by Using Off-Axis Digital Holography (Off-Axis 디지털홀로그래피를 이용한 마이크로히터의 실시간 온도분포측정)

  • Tserendolgor, D.;Baek, Byung-Joon;Kim, Dae-Suk
    • Journal of the Korean Vacuum Society
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    • v.20 no.2
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    • pp.106-113
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    • 2011
  • We describe a single shot off-axis digital holography based on a Mach-Zehnder interferometic scheme for measuring temperature distribution of a microheater. The proposed scheme has the capability of reconstructing object phase image which is dependent of the temperature distribution in real time. Experimental results shows that there is a moderate linear relationship between the measured phase and temperature in the range of $20^{\circ}C$ to $60^{\circ}C$. We expect that the proposed system can provide a very reliable and fast solution in various surface temperature distribution measurement applications.

Visualization of Temperature Distribution Deep Inside the Agar Gel Tissue Phantom Heated Using Moxibustion and 1064 nm Infrared Laser (쑥뜸과 1064 nm 파장의 근적외선 레이저로 가열된 아가젤 조직 팬텀 심부의 온도분포 가시화)

  • Cho, Ji-Yong;Kim, Jung-Kyung
    • Journal of the Korean Society of Visualization
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    • v.8 no.4
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    • pp.54-59
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    • 2010
  • A laser moxibustion therapy device having effect similar to that of traditional moxibustion is being developed using 1064 nm infrared laser. The therapy device allows direct interaction of laser light with the tissue rendering temperature distribution both on the skin surface and deep under the skin. We made a device that could measure temperature of deep under the surface of agar gel tissue phantom using thermocouples. A thermal imaging camera was used to verify results from the temperature measurement device. We compared the characteristics of heat transfer inside the tissue phantom during moxibustion and laser irradiation. The temperature distribution measured by thermocouples was found to be similar to that of distribution given by thermal imaging camera.

Time-dependent Optimal Heater Control in Thermoforming Preheating Using Dual Optimization Steps

  • Li, Zhen-Zhe;Heo, Kwang-Su;Seol, Seoung-Yun
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.4
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    • pp.51-56
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    • 2008
  • Thermoforming is one of the most versatile and economical processes available for shaping polymer products, but obtaining a uniform thickness of the final product using this method is difficult. Heater power adjustment is very important because the thickness distribution depends strongly on the distribution of the sheet temperature. In this paper, the steady-state optimum distribution of heater power is first ascertained by a numerical optimization to obtain a uniform sheet temperature. The time-dependent optimal heater input is then determined to decrease the temperature difference through the direction of the thickness using the response surface method and the D-optimal method. The optimal results show that the time-dependent optimum heater power distribution gives an acceptable uniform sheet temperature in the forming temperature range by the end of the heating process.

Distribution of Cathodic Protection Potential for Concrete Slab Specimens at Diverse Environmental Conditions

  • Jin, Chung-Kuk;Jeong, Jin-A
    • International Journal of Ocean System Engineering
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    • v.3 no.2
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    • pp.90-94
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    • 2013
  • This study represents the recent laboratory results from cathodic protection (CP) system with the use of sacrificial anodes at different environmental conditions (temperature of $10^{\circ}C$ and $40^{\circ}C$). Specimens were slab type with a dimension of $500mm{\times}50mm{\times}100mm$, and concrete cover thickness were 25mm. Zinc mesh and/or bulk type anodes were installed at the center of specimen to confirm the distance that CP system has influences on the specimen to distribute uniform CP current to rebar. Two different kinds of temperature condition were applied to verify the effect of temperature. Experiments were conducted for 60 days, and the distribution of potential and current that supplied from anode to rebar was measured. From the results, CP potential was varied with time, and temperature played an important role in CP potential variations. Current was also changed with time, and current distribution could be improved by installing additional bulk type anode.

Temperature Control and Wafer Temperature Distribution Simulation in RTA System (RTA 시스템에서의 온도제어와 웨이퍼상의 온도분포 Simulation)

  • 조병진;김경태;김충기
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.6
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    • pp.647-653
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    • 1988
  • A rapid thermal annealing system using tungsten halogen lamp has been designed and assembled. A control scheme where the temperature control is executed with calculated wafer temperature by considering the thermocouple delay rather than measured thermocouple temperature,is proposed. This control scheme gives more accurate control of the wafer temperature. In addition, the distribution of transmitted light power to the wafer in the system has been simulated, and lamp interval modification has been able to give more uniform light power distribution. Considering incident light spectrum, absorption, reflection, radiation of silicon, etc., temperature profile has been simulated. When the light power uniformity on the 3" wafer is below 1%, the temperature uniformity is about 2%.

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Research on the Influence of Inter-turn Short Circuit Fault on the Temperature Field of Permanent Magnet Synchronous Motor

  • Qiu, Hongbo;Yu, Wenfei;Tang, Bingxia;Yang, Cunxiang;Zhao, Haiyang
    • Journal of Electrical Engineering and Technology
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    • v.12 no.4
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    • pp.1566-1574
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    • 2017
  • When the inter-turn short circuit (ITSC) fault occurs, the distortion of the magnetic field is serious. The motor loss variations of each part are obvious, and the motor temperature field is also affected. In order to obtain the influence of the ITSC fault on the motor temperature distribution, firstly, the normal and the fault finite element models of the permanent magnet synchronous motor (PMSM) were established. The magnetic density distribution and the eddy current density distribution were analyzed, and the mechanism of loss change was revealed. The effects of different forms and degrees of the fault on the loss were obtained. Based on the loss analysis, the motor temperature field calculation model was established, and the motor temperature change considering the loop current was analyzed. The influence of the fault on the motor temperature distribution was revealed. The sensitivity factors that limit the motor continuous operation were obtained. Finally, the correctness of the simulation was verified by experiments. The conclusions obtained are of great significance for the fault and high temperature demagnetization of the permanent magnet analysis.

A Study on Thermal Performance of Heat Pipe for Optimum Placement of Satellite Equipment

  • Park, Jong-Heung
    • ETRI Journal
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    • v.19 no.2
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    • pp.59-70
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    • 1997
  • A study on the operation of a heat pipe with two heat sources has been performed to optimize the heat distribution of satellite equipment. A numerical modeling is used to predict the temperature profile for the heat pipe assuming cylindrical two-dimensional laminar flow for the vapor, and the conduction heat transfer for the wall and wick. An experimental study using the copper-water heat pipe with the length of 0.45 m has been performed to evaluate the numerical model and to compare the temperature distribution at the outer wall for the non-uniform heat distribution. The results on temperature profiles for the heat input range from 29 W to 47 W on each heater are presented. Also the correlation between the heat input and the temperature increase is presented for the optimum distribution on two heaters. The result shows that the outer wall temperature can be controlled by redistribution of heat sources. It is also concluded that the heat source closer to the condenser can carry more heat while maintaining lower temperatures at the outer wall.

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NUMERICAL OPTIMIZATION OF TEMPERATURE DISTRIBUTION IN HRSG SYSTEM USING INLET GUIDE VANE (전치 가이드 베인 설치에 따른 열회수 보일러 입구 온도 최적화)

  • Lee, Soo-Yoon;Ahn, Joon;Shin, Seung-Won
    • Journal of computational fluids engineering
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    • v.14 no.3
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    • pp.1-8
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    • 2009
  • Diverging channel from gas engine exit to the inlet section of Heat Recovery Steam Generator (HRSG) has been re-designed for 1 MW system. To improve the uniformity in velocity and temperature distribution of existing design(Case A and B), two additional test geometries have been chosen for the numerical simulation. At first, gas burner exit section has been centered to the inlet section of the boiler(Case C) and uniformity in velocity and temperature distribution has been improved considerably. Secondly, the diverging channel length can be further reduced to compact geometry with new guide vane design (Case D and E). Proposed design shows overall improvement in uniformity in velocity and temperature distribution compared to existing one.

A Study on the Detection of Abnormal Tissues in Biological Tissue Using Temperature Distribution According to Light Irradiation (광 조사에 따른 온도분포를 이용한 생체조직 내 비정상조직 탐지에 대한 연구)

  • Ko, Dong Guk;Im, Ihk-Tae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.41 no.5
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    • pp.303-309
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    • 2017
  • In this study, the characteristics of the temperature generated by light irradiation, on the surface of a biological tissue with an abnormal tissue part (paraffin) and at the surroundings of the abnormal tissue were studied by numerical and experimental methods. The temperature in the tissue was solved using the computational heat transfer and was compared with the temperature measured with thermocouples. The effects of the light wavelength and the irradiation time on the temperature distribution were analyzed. As a result, the temperature distribution from the irradiation of light in the biological tissue was different when there was an abnormal tissue part. The temperature in the biological tissue with the abnormal tissue part was higher than in a normal tissue.