• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.11
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• pp.1127-1133
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• 2012

A finned-tube-type evaporator module has been proposed for a 2 t/h-class water-tube-type industrial boiler with multiple burners. The geometry of the fins was changed at each module to equalize the evaporation. The modules were designed by considering the energy balance at each row rather than by following a conventional bulk design procedure. The designed module was built into a 2 t/h-class water-tube-type boiler, and its performance was tested. A numerical simulation was also conducted to evaluate the two- or three-dimensional effects of factors such as the inlet conditions. The numerical simulation also included the conjugate heat transfer problem to predict the fin tip temperature. The heat transfer coefficient with fins is lower than that obtained from the empirical correlation of a bare tube. The fin tip temperature from CFD is higher than that from the analytical solution.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.3053-3058
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• 2008

We develop a heat exchanger modules for a multi-burner boiler. The heat exchanger module is kind of a heat recovery steam generator (HRSG). This heat recovery system has 4 heat exchanger modules. The 1st module consists of 27 bare tubes due to high temperature exhaust gas and the others consist of 27 finned tubes. The maximum steam pressure of each module is 1 MPa and tested steam pressure is 0.7 MPa. In order to test these heat exchanger modules, we make a 0.5t/h flue tube boiler (LNG, $40\;Nm^3/h$). We tested the heat exchanger module with changing the position of each heat exchanger module. We measured the inlet and outlet temperature of each heat exchanger module and calculated the heat exchange rate. The results show that if module C is placed at second stage (the 1st stage is always module O, bare tube module), there is no need to attach an additional heat exchanger module. In this case the exit temperature of module C is low enough to enter an economizer which is more effective in heat recovery than a heat exchanger module.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.788-793
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• 2001

Finite element analysis was carried out to investigate the integrity and reliability of boiler module during sea transportation. The boiler module was supported by steel structure to relieve the instantaneous shock from oceanic wave and its primary parts were strengthened with several reinforcements. Finned tube walls which were used in the furnace wall were assumed as orthotropic plates having equivalent material properties. The bank tubes were also equivalently modeled in accordance with ASME B31.1 for the convenience of finite element modeling. The calculation results were compared with the yield stress of the material. In particular, the bank tube stress, which was evaluated by converting the calculated stresses in equivalent tubes into those in original tubes by using the ratio of diameter, was also examined with yield stress.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.3
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• pp.265-270
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• 2012

A finned tube type heat exchange module has been proposed for a multi-burner water tube boiler. Fin density and length increase in streamwise direction to equalize the evaporation for each module, which makes it difficult to apply conventional bulk design procedure. The design program has been improved by updating data for every row of tubes along the flow. A numerical simulation has been also conducted to evaluate the effect of inlet conditions and validated with experiment. The heat transfer of the first row has been underpredicted by the conventional Zhukauskas correlation, since the acceleration of the flow due to the blockage is not fully inflected. The fin tip temperature is also underpredicted by Bessel solution, because of the interaction with neighboring fins.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.118-120
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• 2019

최근 IoT 모듈 즉, 사물 인터넷 기반 기술에 대한 연구가 활발히 진행되고 있으며, 다양한 제품들이 출시되고 있다. 대표적인 IoT 제품으로 가정에서 인터넷과 모바일 앱을 이용하여 카메라, 전등, 보일러 등을 제어하는 것을 볼 수 있다. 하지만 보통의 IoT모듈은 센서로 값을 추출하는 것이 목적이기 때문에 센서의 정확성과 고장 유 무를 판단하기 힘들다. 본 논문에서는 아두이노와 무선통신, 웹서버, 안드로이드 어플리케이션을 이용해 센서에서 추출된 값을 비교 분석한 표준편차를 이용해 센서의 고장 유 무를 판단 할 수 있는 모바일 앱을 설계 및 구현하고자 한다. 아두이노의 와이파이, 온습도센서 모듈 등을 이용하여 통신 연결을 하고 각종 환경, 제어정보들을 HTTP통신을 이용하여 웹서버와 통신하여 전달하고 제어한다. 이로써 사용자가 직접 IoT모듈에 가지 않아도 스마트폰 어플리케이션을 통해 센서 상태를 모니터링 및 진단하고 고장 유 무를 파악하여 교체시기를 알려주는 기능을 구현하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10b
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• pp.643-645
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• 2004

발전계통 시뮬레이션은 CFO(전산유체역학)을 이용한 시뮬레이션으로서 다차원 미시적인 현상에 대한 시뮬레이션을 뜻한다. 주요 특징으로써 다수의 컴포넌트로 구성된 계통의 다양성으로 보일러, 급수계통, 증기계통, 복수계통 등 다양한 계통들이 존재하고 있다. 따라서 다양한 컴포넌트 모듈을 저장할 수 있는 GUI(Graphic User Interface) 기반의 시뮬레이션 툴이 필요하게 되었다. 현재 발전계통 시뮬레이션 툴의 문제점은 외국의 상용화 툴에 전적으로 의존하고 있으며 이는 곧 시뮬레이터 유지 보수의 어려움을 초래하게 되었다. 본 논문에서는 발전계통 시뮬레이션을 위한 컴포넌트 모듈의 생성, 모듈과 그래픽 라이브러리간의 연결, 유량-압력 알고리즘을 이용한 계통 Solver를 설계하고 멀티스레드를 이용한 복수개의 계통 시뮬레이터 구현 방법을 소개한다.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.8-15
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• 1998

1. 서론 : 중국에서 분리막에 관한 연구는 1965년부터 역삼투막에 관한 연구를 시작으로. 70년대 초기부터는 한외여과막(UF막)에 관한 연구가 수행되었다. 이후 정밀여과막(MF막), 기체분리막(GS막) 등에 관한 연구가 이루어져 수처리 분야 및 기체분리 공정 등에 실용화되고 있다. 특히 80년대 초기부터 10년간으 실험실 연구단계에서 산업화로 넘어온 시기로서 막분리 기술이 크게 발전되었다. 이때에 주요한 연구성과는 다음과 같다. 수행되었다. 1) 호주의 수처리 설비공장과 흥성의 8271공장은 매년 몇 천대의 나권형 모듈을 제조할 수 있는 RO막 생산라인을 건립하고, 국가해양국 항주 수처리기술개발센터의 중공사막 제조라인은 1,000만원/년의 생산능력을 갖고 있다. 2) 대형 중공사막, 나권형 모듈제조 기술이 확립되어, 국산 RO, UF모듈 및 장치는 초순수 제조 및 발전소 보일러 용수의 정화에 사용되어 수입 사용되는 외국장치를 대체하게 되었다. 3) 막분리 기술의 연구 및 응용공정 개발에 관한 연구 인력은 당시 초보적인 소수의 연구원이 형성된 이후, 지금은 전문연구인력이 400여명에 이르고 있다. 본고에서는 중국에서 응용되고 있는 분리막 기술중 RO막, UF막, MF막 및 NF막을 중심으로 기술개발 동향 및 현황을 소개하고자 한다.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.211-221
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• 2016

The increase of world's population and economic development are the keys drivers behind growing demand for energy. Especially the demand for electricity would eventually result in an increase of coal usage. Therefore ultra supercritical circulating fluidized bed boiler has been developed as solutions of economic eco-friendly technologies for coal and of increasing supplies of low grade fuels. Ultra supercritical circulating fluidized bed boiler has an once through type of steam cycle different from drum type in subcritical circulating fluidized bed boiler. Also, the duplication of a proven commercial module with 100-300 MWe subcritical circulating fluidized bed might be the key for design of 500~800 MWe ultra supercritical circulating fluidized bed boiler. After 2017, ultra supercritical circulating fluidized bed boiler might become standard model over subcritical circulating fluidized bed boiler. Therefore, this paper will help you to understand ultra super critical circulating fluidized bed (USC-CFB) through describing the background, status and prospect of the CFB technology.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.528-533
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• 2007

A finned tube type heat transfer module has been proposed for a multi-burner water tube boiler. Fins change their geometry along the streamwise direction to maximize the performance, which makes it difficult to apply conventional bulk analysis. The design program has been improved by updating data for every row of tubes along the flow. A numerical simulation has been also performed to evaluate the effect of inlet conditions and validated with experiment. The heat transfer of the first row has been underpredicted by the conventional Zhukauskas correlation, where the acceleration of the flow due to the blockage is not fully inflected. The fin tip temperature is also underpredicted by Bessel solution, because of the interaction with neighboring fins.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.476-479
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• 1997

The focus of this paper is to implement of virtual plant using module concept for the dynamic simulation of drum type boiler and to simulate the control trends of dynamic characteristics. MAtlab & Simulink is used for implement virtual plant & analyzation the dynamics & control trends. They are available for analyzing the dynamic characteristics of drum type Boiler by means of applying well measured data to virtual plant.