• 동력기계공학회지
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• 제10권4호
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• pp.31-37
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• 2006

In this study, the ability for the function of double pipe inserted liquid pipe with small diameter in the gas pipe with large diameter for the circulating of liquid of high temperature and high pressure and low temperature and low pressure at the same time is presented. And in this double pipe, liquid pipe of high temperature and pressure is used to connect condenser and expansion valve and gas pipe of low temperature is used to connect evaporator and compressor. Also, when liquid refrigerant of high temperature and gas refrigerant of low temperature is circulated by reversed flow in the double pipe. The contribution of liquid gas heat exchange pipe is studied by comparison of the effect of heat transfer by temperature difference when liquid pipe and gas pipe is installed separately.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.681-686
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• 2006

In order to protect the environment from the refrigerant pollution, the $CO_2$ may be regarded as one of the most attractive alternative refrigerants for an automotive air-conditioning system. Control methods for a $CO_2$ system should be different because of $CO_2's$ unique propel-ties as a refrigerant. Especially, the high-side pressure of a $CO_2$ system should be controlled for the effective operation of the system. In this study, dynamic models of a $CO_2$ air-conditioning system were developed by using experimental data. Control algorithms for a high-side pressure control and an indoor air temperature control were developed and analysed by using the dynamic simulation program of a $CO_2$ system.

• 한국산학기술학회논문지
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• 제12권12호
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• pp.5430-5437
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• 2011

본 연구의 목적은 친환경 무공해 승용 차량에 적용되는 전동식 냉방시스템의 성능특성을 실차에서 확인하는 것이다. 이를 위하여 인버터로 구동되는 전동식 스크롤 압축기를 적용한 전동식 냉방시스템을 설계 및 제작하여 수소 연료전지 자동차에 설치하여 다양한 주행도로 조건에서 실험을 진행하였다. 주행조건의 변화는 시험차량에 장착된 전동식 냉방시스템의 성능에 영향을 주었으며, 고속 및 일반도로 주행조건에서 냉방시스템의 성능이 정지조건에서 냉방시스템의 성능보다 우수하게 나타났다. 또한, 외기온도가 $20.0^{\circ}C$에서 $30.0^{\circ}C$로 증가함에 따라 고내 온도는 평균 $5.2^{\circ}C$ 더 적게 감소하였다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2003년도 하계학술대회 논문집
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• pp.103-103
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• 2003

• 한국자동차공학회논문집
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• 제21권6호
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• pp.175-182
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• 2013

Lately, customers think highly of the emotional satisfaction and as a result, issues on odor are matters of concern. The cases are odor of interior material and air-conditioner of vehicles. In particualar, with respect to the odor of air-conditioner, customers strongly claimed defects with provocative comments : "It smells like something rotten," "It smells like a foot odor," "It stinks like a rag." Generally, it is known that mold of evaporator core in the air-conditioning system decays and this produce VOCs which causes the odor to occur. In this study, partial least squares regression model is applied to predict the strength of the odor and select of important VOCs which affect car air conditioning smell. The PLS method is basically a particular multilinear regression algorithm which can handle correlated inputs and limited data. The number of latent variable is determined by the point which is stabilized mean absolute deviations of VOCs data. Also multiple linear regression is carried out to confirm the validity of PLS method.

• 설비공학논문집
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• 제12권3호
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• pp.315-324
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• 2000

R-410A, R-407C, and four refrigerant mixtures composed of R-32, R-l34a, R-l43a, R-l52a, R-600(butane), and R-600a(isobutane) were tested in an attempt to replace R-22 used in most of the residential air conditioners. The performance evaluation was carried out in a psychrometric calorimeter test facility using a residential spilt type air conditioner under the KS rating conditions. Except for the lubricant and hand-operated expansion valve, the other parts of the air conditioner were the same with the commercial system. Performance characteristics were measured; COP, capacity, compressor power, and VCR. R-410A was shown to have 5.5% higher COP and 3.5% lower capacity than R-22. R-32/134a/600a (42.8/ 46.0/11.2 wt%) mixture have the best performance among the four refrigerant mixtures composed of hydrofluorocarbon and hydrocarbon. This inixture have 3.0% lower COP and 1.6% lower capacity than R-22.

• 설비공학논문집
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• 제1권3호
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• pp.203-209
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• 1989

This paper is an experimental study on the pleasantly suitable cool/warm air conditioning system in order to minimize the energy consumption by attaching the electronic-controlled device to the heat pump air conditioning system.While the cool/warm air conditioning, the air temperatures in the entrance and exit of the indoor heat exchangers should be checked and when the surface of heat exchanger is reached to the dew point temperature, a speed of the compressor is to be automatically controlled by anti-dewing system in order to minimize the energy consumption.At the result of this study, the energy consuming amount is saved about 5% more than that of the conventional air conditioning system by prevent unnecessary dew forming.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 하계학술발표대회 논문집
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• pp.110-110
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• 2007

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.480-485
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• 2005

In the respect of the environmental protection viewpoint, the $CO_2$ may be regarded as one of the most attractive alternative refrigerants for an automotive air-conditioning system. Control methods for a $CO_2$ system should be newly developed, because properties of $CO_2$ are different compared with those of classical refrigerants. Especially, high-side pressure of a $CO_2$ system should be controlled for the effective operation of the system. In this study, intelligent control algorithms for a $CO_2$ system were developed ‘ These are a high-side pressure control algorithm and an indoor air temperature control algorithm. These algorithms were analysised by using dynamic models of a $CO_2$ system.

• 한국태양에너지학회 논문집
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• 제32권6호
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• pp.141-148
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• 2012

Ceiling cassette type air conditioner has been a main stream as a heating/cooling system recently in school, Korea. In this study, indoor thermal environments made by ceiling cassette type air conditioner were investigated by CFD simulation. Concentrations of $CO_2$ were investigated by a field measurement. Indoor thermal environment with the velocity inlet angle of $45^{\circ}$ from the ceiling in heating season was very ununiform so that thermal area was divided into two parts those the one is window side which is cold, and the other is corridor side which is hot. In cooling season under the same condition, there are areas too hot or too cold. If the velocity inlet angle is set in $30^{\circ}$ from the ceiling, indoor thermal environments was improved greatly in cooling season and heating season, too. Also, from the field measurement of $CO_2$ concentrations, it was suggested to install ventilators with proper air volume considered the number of class students.