• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.197-201
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• 2001

Output and cost efficiency in the production of hot-rolled strip depend to a large content on the uniformity of geometric and mechanical properties over the length and width of the rolled end product. To ensure the homogeneous temperatures required for this during the rolling process a system to measure and evaluate the transverse temperature profile was developed and implemented in production. The systems used consist of temperature scanners and computers for measurement and data evaluation. The systems have been installed in Kwangyang hot strip mills, in the cases at the exit of the finishing train and at the entry of the coiler. They are used in production to determine the effect of the finishing train and the cooling zone on the technological properties of the hot rolled strip.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2005년도 연구개발 발표회 논문집
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• pp.331-337
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• 2005

This study aims at evaluation of component performance of a commercial micro gas turbine by detailed measurements of various system parameters. A test facility to measure performance of a micro gas turbine was set up. Performance parameters such as turbine exit temperature, exhaust gas temperature, engine inlet temperature, compressor discharge pressure and fuel flow rate were measured. Variations in measured data and estimated performance parameters were analyzed. In addition to overall engine performance, component characteristic parameters including the turbine inlet temperature, the compressor efficiency, the turbine efficiency, the recuperator effectiveness were estimated. Behaviors of the estimated characteristic parameters with operating condition change were examined.

• 한국연소학회지
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• 제9권1호
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• pp.1-10
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• 2004

The results of a series of experiments executed by using two pilot-scale oxy-fuel burners are presented. The oxy-fuel burners are designed for maximum capacity of 50,000kcal/hr, 200,000kcal/hr and installed in the test furnace. The effects of turn-down ratio, excess oxygen ratio, nozzle exit velocity, injection angle, and swirl vane angle on the combustion characteristic are investigated. Temperature distributions are measured using R-type and Molybdenum sheathed C-type thermocouple at various points of the flame. The results showed that maximum temperature and mean temperature increase with the increase of turn-down ratio and momentum. The maximum flame temperature was increased about 35% compared to the case of equivalent air operated condition. In addition, optimum burner type, excess oxygen ratio and nozzle characteristics are obtained for this oxy-fuel glass melting furnace.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.107-108
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• 2013

An experimental study in the dual swirl burner was conducted to analyze the temperature characteristics in the combustion field. The dual swirl burner consists of a main swirling pre-mixed flame with tangential swirler surrounding a pilot which can stabilize a diffusion flame or a partially premixed flame with vane swirler depending on whether fuel is supplied at the exit plane or further upstream. The purpose of this study is to analyse experimentally the characterization of flame temperature in the reacting zone, specially, according to the various combustor diameters like 80mm, 100mm, 130mm and 150mm(O.D). As a result, the temperatures of combustion field were decreased as the diameter of combustor increased. Therefore, these results can be expected that the larger diameter of combustor tend to emit less NOx emission than the small combustor.

• 한국추진공학회지
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• 제8권2호
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• pp.10-17
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• 2004

본 논문에서는 액체로켓엔진용 160 kW급 터보펌프의 터빈을 구동하고, 액체산소와 케로신을 추진제로 사용하는 연료 과잉 가스발생기의 설계점 연소성능시험 결과에 대해 논의하였다. 충돌형 F-O-F 분사기로 구성된 헤드부, 물냉각 채널 연소실, torch igniter, turbulence ring 그리고 측정 링을 갖는 가스발생기에 대해 기술하였고, 설계점에서의 연소시험 및 turbulence ring 장착여부. 연소실 길이 변화에 따른 연소시험의 결과들에 대해 기술하였다. 연소시험 결과 가스발생기는 설계점에서 안정된 작동성을 보여주었고. 연소압력 및 온도 등의 성능은 예측치에 근접하는 결과였다. Turbulence ring은 출구에서의 가스온도를 균일하게 분포시켜 효과적인 혼합 장치임을 보여 주었고, 4∼6msec 정도에서의 연소가스 잔류시간은 연소효율에 큰 영향을 주지 않았다. 가스발생기 출구에서의 온도는 공급되는 추진제의 O/F ratio에 따라 매우 민감하게 변화하였다.

• 항공우주기술
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• 제3권2호
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• pp.81-90
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• 2004

액체로켓엔진에서 터보펌프의 160kW급 터빈 구동용의, 액체산소와 케로신을 추진제로 사용하는 가스발생기의 탈설계점 연소성능시험 결과에 대해 논의하였다. 가스발생기의 탈설계점 연소시험에서 연소압력은 O/F비와 추진제 공급유량의 함수로 나타나는데, 출구 온도편차는 turbulence ring이 있는 경우 ±7.5K 이내로 매우 균일한 공간적 온도분포임을 확인하였다. 각각의 탈설계점 연소시험에서 가스발생기 출구 온도는 가스발생기로 공급되는 추진제의 O/F 비의 함수로 나타낼 수 있었다. 본 가스발생기의 탈설계점 연소시험 결과, 특히 가스발생기의 혼합비와 가스온도와의 관계는 향후 개발되어질 가스발생기 설계나 저혼합비 연소해석 코드를 작성 시 매우 유용하게 사용되어질 것이다.

• 한국축산시설환경학회지
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• 제8권2호
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• pp.79-86
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• 2002

This study was conducted to collect basic data about the effects of ventilation types on the interior environment of the enclosed farrowing-nursery pig house in Anseong, Icheon and Jeungpyong. Surveyed ventilation types in the enclosed farrowing-nursery pig house are classified in to 4 types. In V1 type, air enters through a planar slot inlet placed on the juncture of the entering wall and exit through the chimney fan outlet; in V2 type, air enters through a perforated ceiling inlet and exits chimney fan outlet(V2); in V3 type, air enters through a circular duct inlet and exit chimney fan outlet(V3); in V4 type, enters through a circular duct inlet and exits side wall exhaust fan outlet(V4). Temperature, relative humidity, air velocity and ammonia concentration($NH_3$) were measured in the interior of swine building in the summer. Interior temperature was not remarkably different in all ventilation types in this study. However, temperature of the V4 was somewhat lower than that of the other types. Air velocity of the V4 was higher and $NH_3$ concentration of the V4 was lower than those of other ventilation types. It is suggested that the V4 ventilation type be applicable in the enclosed farrowing-nursery pig house in Korea.

• 한국산학기술학회논문지
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• 제19권8호
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• pp.8-13
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• 2018

질소산화물은 최근에 초미세먼지 발생에 많은 영향을 주고 있어서 대기환경 개선 측면에서 사회적으로도 크게 관심이 되고 있다. 질소산화물은 주로 화력발전 등의 연소기기에서 고온의 연소가스 분위기에서 공기 중의 질소와 산소가 반응하여 발생한다. 이에 대한 저감 방법으로 원통형 버너에 코안다 노즐을 이용한 배관으로 배기가스를 재순환하는 연소에 대한 연구가 최근에 이루어지고 있다. 본 연구에서는 코안다 노즐을 사용하여 배기가스를 재순환하는 원통형 버너의 연소가스 출구의 위치를 오른쪽으로 하는 버너(Case 1 버너), 양쪽을 출구로 하는 버너(Case 2 버너), 왼쪽을 출구로 하는 버너(Case 3 버너) 형상에 대하여 전산유체해석을 통해 연구를 수행하였으며 연소 유동의 압력, 유선, 온도, 연소 반응 속도와 질소산화물의 분포 특성을 비교 분석하였다. 연소반응은 Case 1과 Case 2버너는 연소가스 재순환 유입구가 있는 오른쪽 방향으로 일어나고 Case 3 버너는 혼합가스 유입구 부근에서 일어나고 있었다. 출구에서의 온도는 Case 2버너가 양쪽으로 배출되면서 다른 버너 보다 약 $100^{\circ}C$ 정도 온도가 낮게 나타났으며 출구에서의 NOx 농도는 Case 1버너가 다른 형상 버너 보다 약 20배 크게 나타났다. 이로부터 NOx 저감을 위해서는 배기가스 재순환 버너의 출구는 양쪽으로 배출되게 하거나 연소가스 재순환 유입구 반대 방향으로 배출 되도록 하는 것이 효과적임을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.1937-1941
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• 2007

During a process of a nanoimprint for manufacturing LCD, a small temperature variation on the LCD glass can cause thermal stress and generate unexpected displacement. To avoid this trouble, a precision temperature control unit using thermoelectric modules is appropriate for nanoimprint processes. The unit consists of an air control system, a cooling water control system, and a power control system. The air control system includes a thermoelectric module, thermocouples measuring temperatures of air and a duct-stale fin, and two air fans. The heat generated by the thermoelectric module is absorbed by the cooling water control system. The power control system catches the temperature of the thermoelectric module, and a PID controller with SCR controls the input power of the thermoelectric module. Temperature control performance is evaluated by experiment and simulation. The temperature control unit is able to control the exit temperature about ${\pm}2^{\circ}C$ from the incoming fluid temperature, and the error range is ${\pm}0.1^{\circ}C$. However, the control time is approximately 30minute, which needs further study of active control

• 대한기계학회논문집B
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• 제24권10호
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• pp.1399-1408
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• 2000

A 2-dimensional temperature field measurement technique using PLIF (Planar Laser Induced Fluorescence) was developed and it was applied to an axisymmetric buoyant jet. Rhodamine B was used as a fluorescent dye. Laser light sheet illuminated a two-dimensional cross section of the jet. The intensity variations of LIF signal from Rhodamine B molecules scattered by the laser light were captured with an optical filter and a CCD camera. The spatial variations of temperature field of buoyant jet were derived using the calibration data between the LIF signal and real temperature. The measured results show that the turbulent jet is more efficient in mixing compared to the transition and laminar jet flows. As the initial flow condition varies from laminar to turbulent flow, the entrainment from ambient fluid increases and temperature decay along the jet center axis becomes larger. In addition to the mean temperature field, the spatial distributions of temperature fluctuations were measured by the PLIF technique and the result shows the shear layer development from the jet nozzle exit.