• 태양에너지
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• 제12권1호
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• pp.34-39
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• 1992

본 연구에서는 f-chart method를 이용하여 대전지방에서 공기식 시스템을 적용하였을 경우의 난방효과에 대한 성능 분석을 수행하였다. 공기의 유량, 집열판 덮개의 수, 페블 베드의 축열 용량 그리고 집열판의 코팅 등에 따른 공기식 시스템의 난방 효과를 분석하였으며 아울러 액체식 시스템을 이용한 난방 시스템과도 동일 조건하에서 그 성능을 비교 분석하였다.

• 설비공학논문집
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• 제27권5호
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• pp.269-276
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• 2015

Single-effect $CH_3OH-LiI-ZnBr_2$ and $C_2H_5OH-LiI$ absorption heat pumps are simulated to evaluate feasibility as heating device. These systems are predicted to give higher heating COPs in wide operating ranges compared to conventional systems. Among the two systems, the $C_2H_5OH-LiI$ system is found to be more advantageous for operating in extremely cold weather due to the large solubility of Lil in $C_2H_5OH$.

• 대한설비공학회지:설비저널
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• 제15권3호
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• pp.292-298
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• 1986

The new f-chart capable of estimating long-term thermal performance of solar space and water heating systems was developed. The system comprise a flat plate solar collector, heat exchanger, storage tank filled with water, auxiliary fuel fired heater, and a house structure. The information obtained from many simulations of solar heating systems has been used to develop this f-chart. Actual hourly meteorological data collected in Seoul, Daejeon, Kwangju and Daegu, Korea from 1979 to 1983 have been utilized in these simulations. The new f-equation is as follows: $$f=1.034Y_{-}0.0968X_{-}0.2235Y^2+0.0043X^2+0.0144Y^3$$. The system performance estimates obtained from the developed f-chart are in close agreement with the results of experiment.

• 설비공학논문집
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• 제10권6호
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• pp.773-783
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• 1998

The heating system for apartment complex may be classified as old systems including central system with steam boiler(S1), gas engine driven heat pump system(S2), system using waste heat(S3) and new systems including mechanical vapor re-compression system with flashing heat exchangers(S4), system using methanol(S5), system using metal hydride (S6). The purpose of the present study is to suggest optimal heating system by technically, economically and environmentally evaluating old and new heating systems of apartment complex from 500 to 3,000 households. Economic evaluation based on the technical evaluation results which estimated heat transfer area of heat exchangers and capacity of equipments was estimated initial investment cost, annual operating cost and relative payback period by considering annual increasing rates of energy cost and interest. Environmental evaluation provided annual generation rate of carbon dioxide. Initial investment cost was cheap in the order of S6, S5, S3, S2, S4, S1, annual operating cost was cheap in the order of S1, S2, S4, S5 and relative payback period was short in the order of S6, S5, S2, S3 and S4. Relative payback period was within 8 years for all scenarios of 3,000 households, and was increased as annual increasing rates of energy cost and interest were increased. As transportation pipe length was increased twice, payback period was increased by 1.4~2.6 time. The effect of temperatures of waste gas and waste water on the relative payback period was small within 0.8 years. The annual generation rate of carbon dioxide was big in the order of S4, S2 and S1. S4 was the most economic system among whole scenarios when S1 was replaced with other scenarios.

• 자원ㆍ환경경제연구
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• 제10권3호
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• pp.367-386
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• 2001

In this paper we analyze the environmental advantages of district heating system. We construct three econometric models to analyze the energy consumption and economic cost as well as the emission of the major pollutants like $SO_x$, $NO_x$, DUST, and $CO_2$. As the size of heating supply is larger, the district heating system is evaluated to be better than other heating systems environmentally and costly in the long run. Especially, the district heating reduces $SO_x$ emission significantly when the size of heat production is large. But the advantages of district heating system are very sensitive to the fuel mix and heat source.

• 한국태양에너지학회 논문집
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• 제28권6호
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• pp.64-69
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• 2008

In this study the thermal performance and economic analysis program of solar heating system for district heating was developed. This program, named SOLAN-DHS and based on TRNSYS, consisted of four modules like as user's interface for system input/output, library, and utilities and a calculating engine. SOLAN-DHS simplifies user's input data through the database of most system engineering data including weather data of 17 areas in Korea. Five different types of solar systems which can be applicable to district heating system were presented in this program. Due to the user-friendly layout, all design parameters can be changed quickly and easily for the influence on system efficiency. The reliability of SOLAN-DHS was finally verified by the experiments.

• 설비공학논문집
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• 제23권11호
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• pp.762-768
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• 2011

We use floor radiant heating system in the house of commons in winter Floor radiant heating system, which transfer heat by radiation, is one of the energy efficient and comfortable systems that. Floor radiant heating system is configured to be controlled by the room for energy-saving. Proper flow rate to a comfortable heating in the room is important. However, Using a constant speed circulation pump in separate rooms, heating system may cause an imbalance because of the difference of length of coil when operating in the rooms. In this study, our Research team examined heating imbalance due to the variation length through the coil length changes and flow control of the circulation pump.

• 한국세라믹학회지
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• 제52권2호
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• pp.119-122
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• 2015

Laser sealing with glass frits appears a promising technology for sealing various electronic devices (e.g., solar cells, displays) due to its several advantages. The purpose of this study is to understand the relationship between the composition of glasses and their laser-heating conditions. To allow glass to be sealed using laser heating, CuO was added to two different glass systems, in different amounts. The optical absorptivity of the glass samples was related directly to their CuO content. The laser-heating temperature and the CuO content exhibited a proportional relationship. Furthermore, the heating temperature increased linearly with the laser power used. From these results, we could determine the appropriate laser-heating conditions and CuO content for sealing electronic devices using laser-sealing technology.

• Journal of Ship and Ocean Technology
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• 제6권4호
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• pp.1-12
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• 2002

A control system for an automated line heating process is developed by use of object-oriented methodology. The main function of the control system is to provide real-time heating information to technicians or automated machines. The information includes heating location, torch speed, heating order, and others. The system development is achieved by following the five steps in the object-oriented procedure. First, requirements are specified and corresponding objects are determined. Then, the analysis, design, and implementation of the proposed system are sequentially carried out. The system consists of six subsystems, or modules. These are (1) the inference module with an artificial neural network algorithm, (2) the analysis module with the Finite Element Method and kinematics analysis, (3) the data access module to store and retrieve the forming information, (4) the communication module, (5) the display module, and (6) the measurement module. The system is useful, irrespective of the heating sources, i.e. flame/gas, laser, or high frequency induction heating. A newly developed automated line heating machine is connected to the proposed system. Experiments and discussions follow.

• 태양에너지
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• 제11권2호
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• pp.29-33
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• 1991

본 연구는 일차원 열 성능 분석 프로그램인 SERI-RES를 이용하여 우리 고유의 난방 방식이라 할 수 있는 Radiant Floor Heating System의 운전 모드(Operation Modes)에 대한 시뮬레이션을 수행하였다. SERI-RES는 원래 공기 가열식 시스템을 주요 난방 방식으로 작성된 프로그램이라 본 연구의 시뮬레이션을 수행하기 위하여 Source Code에 대한 약간의 수정을 가하였다. 얻은 결과를 분석하여 보면 Radiant Floor Heating System은 그 운용 방법(Operation Modes)에 따라 건물의 동적 열 성능에 상당한 영향을 미치는 것으로 나타났으며 이는 Test Cell에 대한 간단한 실측 실험을 통해서도 확인되었다. SERI-RES는 비록 HVAC 시스템등에 대한 구체적인 시뮬레이션은 불가하나, 비록 일차원적이기는 하지만 Radiant Floor Heating 시스템과 건물의 동적 열 성능에 대한 분석에는 상당히 효율적인 Simulation Model을 제공하였다.