• Journal of the Korean Society of Industry Convergence
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• v.1 no.2
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• pp.13-19
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• 1998

A computer simulation program for the design of furnace witjin pakaged water-tube boilres is developed and the developed computer program is successfully applied to design the furnace for packaged water-tube boiler. The model by experiment and the model by Hottel are used to predict the exit gas temperature of furnace. The result by two models is discussed and is shown that in the case of constant cross section in furnace, the result is same but in changing the configuration of cross section, the difference by two models is not small.

• Journal of the Semiconductor & Display Technology
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• v.20 no.3
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• pp.103-107
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• 2021

In this paper, a capacitive water level sensor for boilers was developed. In order to accurately monitor the water level in a high-temperature boiler that generates a lot of precipitates, the occurrence of precipitates on the surface of the water level sensor should be small, and a sensor capable of measuring even if the sensor surface is somewhat contaminated is required. The capacitive water level sensor has a structure in which one of the two electrodes is insulated with Teflon coating, and the stainless steel package of the water level sensor is brought into contact with the water tank so that the entire water tank becomes another electrode of the water level sensor. A C-V converter that converts the capacitance change of the capacitive water level sensor into a voltage change was developed and integrated with the water level sensor to minimize noise. The performance of the developed capacitive water level sensor was evaluated through measurement.

• 제어로봇시스템학회:학술대회논문집
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• 1986.10a
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• pp.178-180
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• 1986

본 연구에서는 산업용 팩키지 보일러의 최적한 연소제어를 위하여 O/sub 2/ 제어기의 구성 및 PID제어 알고리즘을 도입하고 그것에 따른 하드웨어 및 소프트웨어를 고찰하였으며 그 결과 하드와이어드 논리제어기나 기존의 PC보다 분산제어의 효율적 처리가 가능하였다. BD/Micro PC 시스템에서 시퀀스 제어를 필요로하는 기능은 BD PC가, 아날로그 시스템을 다루는 PID 제어같은 기능은 .mu.C가 담당함으로서 제어범위가 넓어져 각종의 연산기능확대, BD PC와 .mu.C와의 데이터 링크, 그리고 고장진단등의 기능이 추가되었다.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.225-231
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• 2016

Glasshouse heating package technologies to improve energy usage efficiency in winter were developed. Heating package was composed of the ground water source heat pump with heating capacity of 105kW, the aluminum multi-layer thermal curtain with six layers of different materials and the root zone local heater with XL pipes of ${\phi}20mm$. Venlo type glasshouse($461m^2$) with the heating package was compared with the same type and area control glasshouse with the light oil boiler, the usual non-woven fabric thermal curtain with respect to the glasshouse inside temperature, relative humidity, crop growth, and heating energy consumption. The results of test in paprika cultivation glasshouses showed that the air temperature inside glasshouse with aluminum multi-layer thermal curtain was maintained $2.2^{\circ}C$ higher than that of control glasshouse in un-heating night time and the temperature in bed with root zone local heating was $4.7^{\circ}C$ higher than that in bed without local heating. Average heating coefficient of performance(COP) of the ground water source heat pump used in paprika cultivation was 3.7 and the glasshouse inside temperature was maintained at $21^{\circ}C$ of heating set up temperature. The heating energy consumptions per 10a were measured at 14,071L of light oil and 364kWh of electric power for the control glasshouse and 35,082kWh for the glasshouse applied heating package. As results, the heating cost of the glasshouse applied heating package was 87 percent lower than that of control glasshouse. The growths of paprika in glasshouses of control and applied heating package did not show any significant difference.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.2
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• pp.136-142
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• 2015

The shell and tube heat exchanger is an essential part of a power plant for recovering transfer heat between the feed water of a boiler and the wasted heat. The baffles are also an important element inside the heat exchanger. Internal materials influence the flow pattern in the bed. The influence of baffles in the velocity profiles was observed using a three-dimensional PIV (Particle Image Velocimetry) around baffles in a horizontal circular tube. The velocity of the particles was measured before the baffle and between them in the test tube. Results show that the velocity vectors near the front baffle flow along the vertical wall, and then concentrate on the upper opening of the front baffle. The velocity profiles circulate in the front and rear baffle. These profiles are related to the Reynolds number (Re) or the flow intensity. Velocity profiles at lower Re number showed complicated mixing to obtain the velocities and concentrate on the lower opening of the rear baffle as front wall. Numerical simulations were performed to investigate the effects of the baffle and obtain the velocity profiles between the two baffles. In this study, a commercial CFD package, Fluent 6.3.21 with the turbulent flow modeling, k-${\epsilon}$ are adopted. The path line and local axial velocities are calculated between two baffles using this program.