• Journal of Mechanical Science and Technology
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• 제20권2호
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• pp.278-285
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• 2006

The present study has been conducted to simulate dynamics of a gas engine-driven heat pump (GHP) for design of control algorithm. The dynamics modeling of a GHP was based on conservation laws of mass and energy. For automatic control of refrigerant pressures, actuators such as engine speed, outdoor fans, coolant three-way valves and liquid injection valves were PI or P controlled. The simulation results were found to be realistic enough to apply for control algorithm design. The model can be applied to build a virtual real-time GHP system so that it interfaces with a real controller in purpose of prototyping control algorithm.

• 대한기계학회논문집A
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• 제36권11호
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• pp.1433-1439
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• 2012

본 논문에서는 Building Energy Management System(BEMS) 구현을 위해 "재실자의 위치 및 인원정보" 에 기반을 둔 실내 위치 기반 서비스 및 그를 위한 센서 시스템에 대하여 제안한다. 본 논문에서 제안한 센서 시스템에는 열에너지 그 자체를 감지 할 수 있는 서모파일 센서와 비 접촉 방식으로 대상까지의 거리를 얻어낼 수 있는 초음파센서, 그리고 이를 제어하고 구동할 수 있는 기구 및 동작부가 포함된다. 본 시스템은 적절한 크기의 방 전체를 감시할 수 있도록, $360^{\circ}$ 회전과 틸팅이 가능한 구조로 되어있어, 실내공간내의 재실자의 인원 및 위치를 동시에 파악할 수 있다. 또한 무선통신 기술인 블루투스 모듈을 통해 빌딩 관리자나 스마트 홈 서버와의 통신이 가능하도록 되어 있어, 빌딩내의 조명이나 공조시스템을 자동으로 제어, 관리하게 함으로써 전체 에너지 절약을 가능케 한다. 마지막으로 측정 데이터 검증을 위한 실환경 실험을 통해, 본 연구에서 제안한 시스템의 효용성 및 타당성을 확인한다.

• 대한기계학회논문집B
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• 제32권4호
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• pp.275-282
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• 2008

In Korea, air source heat pump system is less efficient than conventional heat source facilities, because the air temperature in winter season is so low that COP of air source heat pump system drops below 3.0. Therefore, the study on the application of heat pump heating and cooling systems is crucial for the efficient popularization of heat pump. In this work, we present the dynamic analysis of energy consumption for the large hospital building by heat resistance-capacitance method. The system simulation of water storage air source heat pump is additionally performed by changing sizes and locations of the hospital building. The computed results show that energy cost of water storage air source heat pump is low, so it is more economical than absorption chiller & heater.

• International Journal of Air-Conditioning and Refrigeration
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• 제6권
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• pp.1-13
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• 1998

The basic heat transfer process that occurs in a building can best be illustrated by an electrical circuit network. Present paper reports the dynamic simulation of annual energy consumption in an office building by the thermal resistance capacitance network method. Unsteady thermal behaviors and annual energy consumption in an office building were examined in detail by solving the simultaneous circuit equations of thermal network. The results are used to evaluate the accuracy of the modified BIN method for the energy consumption analysis of a large building. Present thermal resistance-capacitance method predicts annual energy consumption of an office building with the same accuracy as that of response factor method. However, the modified BIN method gives 15% lower annual heating load and 25% lower cooling load than those from the present method. Equipment annual energy consumptions for fan, boiler and chiller in the HVAC system are also calculated for various control systems as CAV, VAV, FCU+VAV and FCU+CAV. FCU+CAV system appears to consume minimum annual energy among them.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.586-589
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• 2009

This paper presents the performance of a water-to-refrigerant type ground source heat pump (GSHP) system installed in a school building in Korea. For analyzing the performance of the GSHP system, we monitored various operating conditions, including the outdoor temperature, the ground temperature, and the input power of the GSHP system. The average cooling coefficient of performance (COP) of the heat pump was found to be 8.5 at 60% partial load condition, while the overall system COP was found to be 5.9. The average heating COP of the heat pump was found to be 6.5 at 45% partial load condition, while the overall system COP was found to be 5.0.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.903-908
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• 2006

Building energy simulation has become a useful tool for predicting cooling, heating and air-conditioning loads for facilities. It is important to provide building energy performances feed back to the mechanical and electrical system operator and engineer for energy conservation and maintenance of building. From this research, we set up the typical weather data of location, basic description of building, geometric modelling data and the specification of Installed primary HVAC system for establishing the simulation model about energy consuming that take place in multipurpose building complex. The simulation tool of building energy - EnergyPlus (DOE and BLAST based simulation S/W), it has been used and accomplished calculations and analyses for evaluating the effect of the system types and operating condition of central HVAC plant on the building energy consumption. In this paper, we offer comparison and simultaneous results those involve electricity consumption pattern and amount between actual operation versus EnergyPlus simulation to the object building during summer season.

• Wind and Structures
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• 제16권1호
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• pp.61-91
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• 2013

An analytical model of internal pressure response of a leaky and quasi-statically flexible building with a dominant opening is provided by including the effect of the envelope external pressure fluctuations on the roof, in addition to the fluctuating external pressure at the dominant opening. Wind tunnel experiments involving a flexible roof and different building porosities were carried out to validate the analytical predictions. While the effect of envelope flexibility is shown to lower the Helmholtz frequency of the building volume-opening combination, the lowering of the resonant peak in the internal and net roof pressure coefficient spectra is attributed to the increased damping in the system due to inherent background leakage and envelope flexibility. The extent of the damping effects of "skin" flexibility and background leakage in moderating the internal and net pressure response under high wind conditions is quantified using the linearized admittance functions developed. Analytical examples provided for different combinations of background leakage and envelope flexibility show that alleviation of internal and net pressure fluctuations due to these factors by as much as 40 and 15% respectively is possible compared to that for a nominally sealed rigid building of the same internal volume and opening size.

• 설비공학논문집
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• 제23권12호
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• pp.828-835
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• 2011

The purpose of this study is to analyze and evaluate the 3 types of indoor ventilation methods such as natural, mechanical, and hybrid ventilation in high-rise building which is affected by stack effect and outdoor air pressure. For the evaluation of the ventilation capacity, CFD simulation was performed in a typical high-rise residential building. The results of the simulations are as follows: 1) Natural ventilation method is not enough to the regulation. 2) In case of mechanical ventilation, congested area is occurred but meets the regulation. 3) In case of hybrid ventilation with stack effect, all the areas of indoor meet the regulation and congested area is reduced. 4) In case of high-rise building, the differences of ventilation rate among houses in the building are not large because the mechanical ventilation is main factor.

• 한국건축시공학회지
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• 제22권2호
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• pp.195-205
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• 2022

본 연구에서는 BIM(building information modeling)을 활용한 비용 기반 MEP(mechanical, electrical, and plumbing) 조율 프로세스를 제안하였다. 제안된 프로세스는 MEP 부재간 간섭 해결뿐만 아니라 MEP 조율 과정에서 의사결정에 따른 MEP 관련 비용 변화를 정확하고, 빠르게 분석하고, 참여자와 공유할 수 있도록 해준다. 이를 위하여 MEP BIM 모델로부터 추출된 물량 정보와 비용 데이터베이스, 시간 정보를 통합했다. 제안된 프로세스의 적용성을 평가하기 위하여 국내 건설 프로젝트 현장에 적용하였다. 적용 결과, 예상 비용 대비 약 1.6%의 MEP 관련 비용을 절감했다고 분석되었다.

• Smart Structures and Systems
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• 제16권5호
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• pp.807-833
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• 2015

While tuned mass dampers are found to be effective in suppressing vibration in a tall building, integrating it with a semi-active control system enables it to perform more efficiently. In this paper a forty-story tall steel-frame building designed according to the Canadian standard, has been studied with and without semi-active and passive tuned mass dampers. The building is assumed to be located in the Vancouver, Canada. A magneto-rheological fluid based semi-active tuned mass damper has been optimally designed to suppress the vibration of the structure against seismic excitation, and an appropriate control procedure has been implemented to optimize the building's semi-active tuned mass system to reduce the seismic response. Furthermore, the control system parameters have been adjusted to yield the maximum reduction in the structural displacements at different floor levels. The response of the structure has been studied with a variety of ground motions with low, medium and high frequency contents to investigate the performance of the semi-active tuned mass damper in comparison to that of a passive tuned mass damper. It has been shown that the semi-active control system modifies structural response more effectively than the classic passive tuned mass damper in both mitigation of maximum displacement and reduction of the settling time of the building.