• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.525-530
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• 2008

In the present study, the cooling performances of the air-conditioner applied the fin-tube and aluminum PF heat exchangers have been experimentally investigated by using the calorimeter. The experiment is carried out in the conditions of the standard temperature and the low temperature. Fin type of PF heat exchanger is a triangler and squarer form. PF heat exchanger has smaller refrigerant weight and larger capacity and COP han the fin-tube heat exchanger. The performance of PF-2 heat exchanger with the squarer in is more excellent than that of PF-1 heat exchanger with the triangler fin. The high pressure of PF heat exchanger decreases about 7%, compared to the fin-tube heat exchanger. Also, CSPF of the fin-tube and PF heat exchanger is evaluated.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.537-540
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• 2008

A numerical study has been carried out on the optimization of an air cleaning system which was installed in a heating, ventilation and air conditioning system (HVAC) system of subway station for particle removal. Required particle removal efficiencies of three different air cleaning systems were calculated from ventilation rate, and indoor/outdoor concentration of PM10. Mass balance equations of PM10 were used to solve the required particle removal efficiencies. Fibrous filter was considered as an air cleaning system. Calculations were carried out about two different places which were waiting area and platform of subway station, respectively. This study proposed optimized design and operation condition of each air cleaning system.

• 설비공학논문집
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• 제3권4호
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• pp.297-305
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• 1991

Recently, automotive air conditioning system manufacturers have been made a great efforts on the system compactness and high efficiency. This growing interest comes improvements in evaporator thermal performance, one of the most important factors affecting the performance of air conditioning system. In order to improve design of compact type evaporator, this study executes performs to develop a computer program for evaporator thermal performance prediction of automotive air conditioning system. The brief summaries of this study are as follows: 1) To predict the overall thermal performance of serpentine type evaporator, the new simulating method is developed. 2) The calculations are performed as functions of oil mass concentration and refrigerant two-phase distribution at inlet manifold of evaporator. 3) The validity of this simulating program is confirmed by comparing the predicted thermal performance results to experimental results of practical available evaporator. 4) Based on these results, suggestions are made to improve the thermal performance of evaporator.

• 설비공학논문집
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• 제20권11호
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• pp.711-717
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• 2008

Despite the fact that UFAD(Under Floor Air Distribution) systems have many benefits and are being applied in the field in increasing numbers, there is a strong need for an improved fundamental understanding of several key performance features of these systems. This study numerically investigates the effect of supplied air temperature and supplied flow rate on the performance of UFAD, especially focused on thermal comfort. Also this study has compared UFAD with conventional overhead air distribution system. In contrast to the well-mixed room air conditions of the conventional overheat system, UFAD system produces an overall floor-to-ceiling airflow pattern that takes advantage of the natural buoyancy produced by heat sources in the occupied zone and more efficiently removes heat loads and contaminants from the space. Thermal comfort parameters were evaluated by CFD approach and then PMV was computed to detect the occupants' thermal sensation. Results show that radiative mean temperature plays crucial role on the evaluating PMV. Until now, the radiative temperature has been the missing link between CFD and thermal comfort, but the present study paves the way for overcoming this weakness.

• 설비공학논문집
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• 제25권5호
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• pp.255-260
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• 2013

Since a chilled beam system can reduce the conveyance energy for air conditioning and has many advantages in terms of constructability and indoor environment, its supply has been rapidly expanding mainly in Europe. For this chilled beam system to be effectively available in Korea, a product suitable for the domestic climatic environment and HVAC system operating conditions needs to be developed. Also, domestic products need to have an edge in cost competitiveness compared to overseas products. In this study, the induction structure of a chilled beam is deduced and an analysis on the induction performance is carried out while the chilled beam system that meets domestic situations is in the process of development.

• 설비공학논문집
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• 제18권5호
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• pp.426-433
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• 2006

The requirements for the optimal building system design is numerous. However, most system designers do not take care of various design strategies. They often argue that the proper simulation tools are not existed to solve the implicated design requirements and the time to consider many alternatives of building systems are insufficient. The aim of this study is to develop the optimization interface program that considers various system design variables and eventually find both the optimal values of annual energy use and cost. Therefore, Doe2Opt is developed to easily perform simulation-optimization process based on DOE2 and GenOpt, and minimizes energy cost of small-to-medium sized building for 6.7% and that of large sized building for 3% with optimizing several HVAC system variables.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.29-34
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• 2006

Although the importance of good conservation of historic sites including ancient royal tombs is well aware, still not much attention has been paid for the facilities and systems to preserve those historic sites, which includes precious artifacts as wall paints and carved works, etc. Even the level of general understanding about the environment of the underground space of tombs is not satisfactory. In Korea, researchers have recently begun addressing the importance of maintaining proper environment for underground space as of ancient tombs and are making efforts to develop suitable HVAC(heating, ventilating and air-conditioning) systems for them. In this study, an HVAC system for a tomb ($D{\times}W{\times}H=1.3m{\times}3.0m{\times}1.2m$) was installed to maintain suitable indoor conditions for conservation of tomb. The temperature and humidity inside the tomb were measured to represent the performance of the installed duct-type HVAC system. Vibration levels due to the installed an HVAC system are alive investigated experimentally. According to the measured data, the level of vibration inside the present model tomb with the duct-type unit showed significantly lower values than the case with the indoor unit inside.

• 설비공학논문집
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• 제16권12호
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• pp.1218-1226
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• 2004

This paper presents thermal behaviors and performances of a fresh air load reduction system by using earth tube system combined with air-heated solar collector. The earth tube system reduces a fresh air load by heat exchange with soil throughout the year. In the previous experimental research, it was clarified that the earth tube system was very useful as a fresh air load reduction system. However, since outlet temperature of the fresh air which was heated by earth tube system was below 15$^{\circ}C$ in winter, it is not suitable to introduce the fresh air into the place of residence directly. Therefore, a simulation model using the simple heat diffusion equation was used to examine a rising effect of outlet air temperature in winter by combining with air-heated solar collector. An improvement of annual performance by control of operation is also quantitatively examined. In conclusion, it is confirmed that its performance is improved by control of operation throughout the year and outlet air temperature rose by combining with air-heated solar collector.

• 대한설비공학회지:설비저널
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• 제28권1호
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• pp.31-37
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• 1999

최근의 건축물은 입구부분에 외부의 광장개념을 실내로 유입시켜 이용객에게 개방감을 주면서 휴식공간을 제공하고자 하는 아트리움 또는 대공간의 형태가 자주 계획되어 지고 있다. 인천국제공항의 첫 관문이자 교통시설의 중심 역할을 하게 될 교통센타에서도 바닥면적 28,000$m^2$, 높이 약45m규모의 대공간이 계획되었으며, 그의 외부형태는 그림 1과 같이 항공기와 새의 모습을 형상화하고 있다. 인천국제공항 단지 내에 위치하고 있는 교통센타는 연면적 9만5천평의 규모로서 앞서 설명한 대공간의 홀과 각종 판매시설, 주차장, 철도역사시설 둥을 갖추고 있다.

• 항공우주기술
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• 제4권2호
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• pp.126-134
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• 2005

발사체는 발사되기 수일 전에 발사탑에 세워져 체크과정 및 연료공급 등을 수행하게 되므로 발사까지는 계속 외부의 열환경에 노출되게 된다. 발사체의 페어링에 대한 발사전 가열 해석(Prelaunch Thermal analysis)은 발사시 페어링의 최대/최소 온도 예측 및 공조 설비(air conditioning system)의 성능 예측을 목적으로 수행된다. 본 연구에서는 범용 열해석 프로그램인 Sinda/Fluint 이용하여 Delta II 페어링에 대하여 발사전 가열 해석을 수행하였으며, 그 결과를 Delta II 보고서 자료와 비교 및 분석하였다.