• 제어로봇시스템학회논문지
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• 제13권4호
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• pp.365-370
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• 2007

This paper studies an automation problem of a heating, a ventilating, and an air conditioning (HVAC) for the development of smart space. The HVAC system is described by the fuzzy system for the stability analysis and the controller design. The linear matrix inequalities (LMIs) conditions are derived for the stabilization problem of the closed-loop system under the analog control. Also, it is required to digitally redesign the pre-designed the analog HVAC control system in order to accomplish the remote control via web. It is shown the this digital redesign problem can be converted to the convex optimization problem with the LMI constraints. An example is provided to show the effectiveness of the proposed method.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.588-593
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• 2011

The Main design parameters of ship HVAC systems are pressure drop and noise analysis of ducts. The Noise prediction for HVAC(Heating, Ventilating and Air Conditioning) systems are normally performed by empirical method suggested by NEBB(National Environmental Balancing Bureau, 1994), but NEBB's method is not suitable for the ship HVAC systems. In this paper, numerical analysis methods are used to develop a noise prediction method for the ship HVAC systems, especially for large ducts. To develop regression formula of attenuation of sound pressure level in large duct, Boundary Element Method(BEM) is used. Using dynamic loss coefficient which is suggested by ASHRAE fitting data base and numerical methods of HVAC noise analysis, integrated HVAC noise analysis of Program is developed. The developed program can present pressure drop and noise analysis of the ship HVAC systems. To verify the accuracy and convenience of the developed program, prediction of HVAC system for Semi-Submersible Drilling RIG is carried out and the results are compared with measurement of noise level during sea trial.

• 한국소음진동공학회논문집
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• 제19권1호
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• pp.101-108
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• 2009

This paper presents dynamic analysis of HVAC(heating ventilation & air conditioning) heater case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC heater case, finite element model which consists of shell elements is constructed for modal analysis and experimental modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model. After identifying mode shape and natural frequency of HVAC heater case, local stiffness of HVAC case is evaluated through point mobility using finite element analysis and experiment.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.378-384
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• 2008

This Paper presents dynamic analysis of HVAC(Heating Ventilation & Air Condition) Heater Case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC Heater Case. finite element model which consists of shell elements is constructed for modal analysis and experimental Modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model After identifying node shape and natural frequency of HVAC Heater Case, local stiffness of HVAC Case is evaluated through point mobility using finite element analysis and experiment.

• 한국통신학회논문지
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• 제32권11B호
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• pp.655-662
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• 2007

건물의 공조설비(HVAC: Heating, Ventilation and Air Conditioning)를 최적으로 운영하기 위해 현재 사용되고 있는 감시 시스템은 운영 설비의 고장이나 성능저하와 같은 결함이 발생할 경우 적절하게 고장을 검출 할 수 있는 기능이 없으며, 이에 따라 고장의 신속한 처리 및 최적 운영이 불가능하다. 이 논문에서는 특정 건물이나 시스템에서만 적용할 수 있는 모델기반 방식의 고장 검출 방법과는 달리 공조기 시스템을 구성하는 저비용이 소요되는 센서 등의 설치를 통해 건물의 공조 시스템에 포괄적으로 적용될 수 있는 분류형 규칙 기반 방식의 고장 검출 시스템을 개발하였다. 또한, 이 알고리즘을 이용한 실험 수행을 위하여 인공기후 실험 동(environment chamber, EC) 내부에 설치된 시험주택(in-house)의 공조 설비 시스템에 적용하여 그 실효성을 검증하였고 향후, 관련 분야에 적용 가능성을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.1923-1924
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• 2006

본 논문은 HVAC(heating, ventilating, and air conditioning) 시스템에 대하여 Multi Fuzzy 제어기 설계를 제안한다. HVAC 시스템은 Compressor(압축기), Condenser(응축기), Evaporator(증발기), Expansion Valve 로 구성되며, 각각의 기기에 대한 제어가 독립적으로 이루여져 있다. 기존의 제어가 한 제어기를 사용한 단일방식으로 이루어지다보니 HVAC 시스템의 특성인 냉매의 상태가 달라지면 시스템 전반적으로 그 영향이 파급되는 부분까지 고려를 해 주지 못하고, 제어기의 성능이 효율적이지 못했다. 본 논문에서는 비선형성이 강하고 불확실하며 복잡한 시스템을 쉽게 제어할 수 있는 Fuzzy 제어기를 구성하여 Expansion Valve 와 Compressor 에서 동시에 제어하는 Multi 제어기를 설계한다. 제안된 Multi Fuzzy 제어기는 HVAC 시스템의 효율성과 안정성에 기초하여, 과열도와 저압을 제어한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.514-520
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• 2000

Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of HVAC(Heating, Ventilating and Air-Conditioning) for Mugunghwa passenger car. The HVAC system is installed under the floor of carbody. This new HVAC system has a lot of merits in respect of the center of gravity of carbody, flow induced noise and reduction of condensation water etc. The standard k-epsilon turbulent model and SIMPLEC algorithm based on finite volume method are used to solve the physical HVAC model. To assure convergence, QUICK scheme for momentum equation and the first order upwind scheme for turbulent equations are used. From the results of simulation, the temperature and velocity magnitude are also distributed uniformly in the interior of car.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.358-362
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• 2003

Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of HVAC(Heating, Ventilating and Air-Conditioning} for double-deck train. The HVAC system is installed under the roof of carbody. In the lay-out of HVAC system, air duct must be installed to supply air to 1st and 2nd floor respectively. The standard k-epsilon turbulent models and SIMPLEC algorithm based on finite volume method are used to solve the physical HVAC model. To assure convergence, QUICK scheme for momentum equation and the first order upwind scheme for turbulent equations are used. From the results of simulation, the temperature and velocity magnitude are also distributed uniformly in the interior of passenger car.

• 한국지열·수열에너지학회논문집
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• 제7권1호
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• pp.32-37
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• 2011

In this study, control characteristics and energy performance with flow rate control methods were reviewed with the simulation. The heating system is classified such as fan coil unit and HVAC system currently used in buildings with valve control and pump inverter control. The simulation analysis program is made by TRNSYS ver. 15 with the actual data. As a result of this study, the central heating system with pump inverter control decreases electricity energy and reduces gas consumption. Inverter control method shows better performance in comparison with valve control one for energy saving.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2989-2994
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• 2008

The shopping center in underground passage for efficient space utilization is increased in urban area. This study describes operation characteristics of HVAC systems with ventilation and individual heating and cooling unit for shopping center in underground passage. In order to compare energy saving, thermal environment and installation space, etc., an integrated simulator with heat production and distribution system was designed and constructed. Energy delivery efficiency is improved over 20%, and energy saving of the hybrid system is calculated as over 30% compared to conventional all air type in the case of heating. And also the results showed that humidity decreased about $5{\sim}6%$, also characteristics of thermal control is improved over 34%.