• Journal of Power System Engineering
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• v.10 no.1
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• pp.71-76
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• 2006

This paper aims to study several type heaters which are mica heater, film heater, quartz heater and rod heater and to get an temteraturel and electrical characteristics. These four type heaters have a merit in many fields than present electric heater with nichrome wire. Carbon and mica plate heater have higher heat efficiency and less electromagnetic waves. Also it has been reported that far infrared ray emission from this heater is good for our health. Additionally heating element is thin and lighter plate. For these reasons, they will be widely used to various application such as room-heating or manufacturing goods. Experimental result confirmed that when 220V current authorized, the temperature, electric current, electric power and the resistance rise to stationary state in early stage. Moreover, the temperatures and electric characteristics show a good stability.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.292-296
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• 1992

There are lots of disturbance in the super heater temperature control system of power plant boiler as follows. 1.Burner light off. 2.Excess Air. 3.Burner tilt. 4.G.R fan flow. Temperature control system of super heater in the power plant has delay time about 5 min. So it is difficult to control the super heater temperature in the power plant. This paper show us the application of domestic development DCS to control the super heater temperature in seoul #5 thermal power plant unit.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2310-2312
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• 2004

In Korea Electric Power Corporation (or KEPCO), several Demand-Side Management (or DSM) program have been carried out to effectively meet electric power demand at least costs by modifying customers electricity use patterns. As one of them, KEPCO applies low-priced night thermal-storage power service for heat appliances to facilitate efficient use of power facilities by shifting relatively high daytime demands to night hours to build loads during the off-peak periods. In the market of heat-storage type water-heater, electric water-heater has been mostly used, but it has low energy efficiency and needs high capacity electric equipments. So in order to replace these electric water heaters, 15 HP air-source heat pump water heater is developed in Korea Electric Research Institute (or KEPRI). This paper shows that measurement system for performance testing of heat pump water heater is established and heating capacity and performance is analyzed and measured for out-door environmental change.

• Proceedings of the KIPE Conference
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• 2019.07a
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• pp.265-266
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• 2019

This paper proposed a three-channel transformer-type power regulator to control the heater temperature by adjusting the voltage across the heater for pre-heating and the post-heating procedures of the material welding. The experimental results are carried out to verify the performance of three-channel heater temperature control for the heat treatment.

• Progress in Superconductivity and Cryogenics
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• v.6 no.1
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• pp.43-48
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• 2004

This paper deals with design and fabrication of heater-triggered switching system for the high-Tc superconducting (HTS) power supply with series-connected double-pancake load. Amongst all components, heater triggering is the most important element for the performance of HTS power supply. To fabricate the optimal heater-triggered system, its characteristics have been analysed through the simulation and expriment. The thermal analysis of switching parts of the Bi-2223 solenoid according to the heater input was carried out. Based upon the analysis, 8A electromagnet current and 1.5A DC Heater current were optimally derived, and 8s and 20s for the pumping period were selected in this experiment. In the experiment. the maximum pumping current reached about 24A with Bi-2223 pancake load of 6mH.

• Journal of computational fluids engineering
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• v.10 no.3 s.30
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• pp.63-69
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• 2005

The COMS, the first meteorological geostationary satellite in Korea, is under development by KARI. The radiator size and the heater power for the thermal control of COMS are calculated using an analytic method. The total radiator area of $4.85\;m^2$ and the total heater power of 794.77 W are determined at a conceptual design of COMS. The commercial software, SINDA and TRASYS, are utilized in order to compare and verify the analytic results. The results of on-orbit numerical simulation of cold and hot cases show that the radiator size and heater power obtained from the analytic method are appropriate to maintain COMS equipments within required temperature ranges.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.5
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• pp.179-184
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• 2018

To lessen oxygen concentrations in a wafer through modifying the length of graphite heaters, we investigated the influence of relative distance from heater to quartz crucible on temperature profile of hot-zone in Czochralski silicon-crystal growth by simulation. In particular, ATC temperature and power profiles as a function of different ingot body positions were investigated for five different heater designs; (a) typical side heater (SH), (b) short side heater-up (SSH-up), (c) short side heater-low (SSH-low), (d) bottom heater without side heater (Only-BH), and (e) side heater with bottom heater (SH + BH). It was confirmed that lower short side heater exhibited the highest ATC temperature, which was attributed to the longest distance from triple point to heater center. In addition, for the viewpoint of energy efficiency, it was observed that the typical side heater showed the lowest power because it heated more area of quartz crucible than that of others. This result provides the possibility to predict the feed-forward delta temperature profile as a function of various heater designs.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.6
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• pp.618-625
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• 2005

This paper has achieved that an optimal design and experiments of heater and cathode of electron gun that serve to embody high current density in CRT display. For the high brightness, high resolution and larger size in CRT display, high current density of electron gun is indispensible. An Impregnation style cathode is used, and must heighten operating temperature of heater to get high current density for this, it is proportional hereupon and power dissipation increases. In this paper, to get low power cathode with high current density, There are produced and tested sample that differ lead type of heater, coating method, the pitch and number of winding of the first and second coiling in the heat emission area for the low power design of high current density cathode heater in this paper.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.5
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• pp.465-469
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• 2010

Air heater used in power plant helps increase the thermal efficiency of the boiler by recovering the heat from the boiler flue gas and thus preventing the loss of useful heat. This study investigates the effect of preventive maintenance on the performance of the air heater in a power plant. Performance indexes for the air heater are calculated to observe the changes in the performance and operation status of the air heater before and after preventive maintenance. The major performance indexes considered are temperature efficiency of the flue gas side, air leakage rate, heat recovery rate, heat transmission rate, and heat capacity ratio. The performance of the air heater is evaluated before and after preventive maintenance; our results show that all the abovementioned performance indexes are improved after the maintenance.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2528-2533
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• 2007

Thermoforming is one of the most versatile and economical processes available for the manufacturing polymer products. The drawback of thermoforming is difficult to get uniform thickness of final products. For the distribution of thickness strongly depends on the temperature distribution of sheet, the adjustment of heater power is very important In this paper, an optimization study for getting uniform temperature distribution was carried out using dual optimization steps. At first, the steady state optimal distribution of heater power is searched by numerical optimization to get uniform temperature of sheet surface. In the second step, time-dependent optimal heater inputs have been found out to decrease the temperature difference through the direction of thickness using Rseponse Surface Method and D-optimal method. The optimization results show that the time-dependent optimal heater power distribution gives acceptable uniform sheet temperature in the field of forming temperature..