• 설비공학논문집
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• 제19권11호
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• pp.761-769
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• 2007

The purpose of this study is to present a simplified model of predicted mean vote (PMV) using multiple regression analysis. We performed the experiments and the numerical calculations in the lecture room during summer and winter to simplify PMV. And the multiple regression analysis on PMV was conducted to estimate the contribution of independent variables toward PMV. From the multiple regression analysis, we found that the effect of independent variables on PMV followed in order, clo value>air temperatur>air velocity>mean radiant temperature>relative humidity. And the simplified PMV was proposed through a few assumptions and then was compared with original PMV. They had a good agreement with each other. Additionally, we compared the simplified PMV with EDT. We expected that the simplified PMV can be more useful than EDT to evaluate the thermal comfort in the place, where radiation is dominant. But the comfort range of the simplified PMV should be adjusted to predict the exact thermal comfort in the future.

• 대한기계학회논문집B
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• 제29권7호
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• pp.868-877
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• 2005

We performed the experimental and the numerical study on the comparison of thermal comfort performance indices for cooling loads in the lecture room for 4 cases: Fan coil unit(FCU) or 4-way cassette air-conditioner is respectively operated with the ventilation system or without. We measured the velocity, the temperature distribution and predicted mean vote(PMV) value in the lecture room for 4 different air-conditioning methods. Effective draft temperature(EDT) and PMV were investigated to analyze the characteristics of two thermal comfort indices in the lecture room and to compare their values each other. From the results we knew that there is the similarity between PMV values and EDTs when the room is air-conditioned for cooling loads. It turned out that definition of the control temperature is very important when the EDT is calculated. Finally EDT should not be used to predict the accurate thermal comfort in case that the temperature and humidity are suddenly varied and the zone affected by the solar and inner wall radiation.

• 토지주택연구
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• 제1권1호
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• pp.19-25
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• 2010

최근 에너지 절약을 화두로 건물에서의 에너지 절약기술들이 크게 요구되어 지는 반면 재실자의 온열쾌적환경은 비교적 비중 있게 다루어지지 않고 있다. 실내공간의 쾌적성은 재실자의 만족감과 더불어 생산성을 향상시키는 등의 역할을 하며, 최근 삶의 질 향상 등에 따라 그 필요성이 크게 요구되고 있는 실정이다. 따라서 본 연구에서는 공동주택을 대상으로 겨울철 난방 시 쾌적지표를 통한 실내 온열환경 제어의 타당성을 검토하고자 시뮬레이션을 수행하였으며, 주거건물에서의 일상적인 실내온도와 에너지 절약 설계기준에서 제시한 실내 설정온도, 그리고 쾌적지표를 설정으로 한 각 제어조건의 온열환경과 에너지 소비량을 비교 분석 및 검토하였다. 본 연구결과에 따르면, 쾌적지표인 PMV로 실내환경을 제어했을 때 에너지 절약설계 기준인 $22^{\circ}C$로 실내온도를 설정하였을 때보다 에너지 소비량은 29% 증가하지만 주거용 건물에서 일반적으로 유지되는 실내온도인 $24^{\circ}C$ 보다는 에너지소비량은 11% 정도 감소하며, 온열쾌적감도 각 제어조건 중 가장 우수하게 나타났다. 따라서 여러 가지 제어변수들을 통한 연구가 지속된다면 주거용 건물에서도 쾌적지표를 활용한 실내 공간의 제어방법은 건물의 에너지를 절약하고 실내 환경의 쾌적성을 증대시키는 주요기술이 될 수 있을 것으로 기대된다.

• 대한전기학회논문지:전력기술부문A
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• 제55권10호
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• pp.399-409
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• 2006

This paper presents a novel method for satisfying the thermal comfort of indoor environment and reducing the summer peak demand power by minimizing the power consumption for an Air-conditioner within a space. Korea Electric Power Corporation (KEPCO) use the fixed duty cycle control method regardless of the indoor thermal environment. However, this method has disadvantages that energy saving depends on the set-point value of the Air-Conditioner and direct load control (DLC) has no net effects on Air-conditioners if the appliance has a lower operating cycle than the fixed duty cycle. In this paper, the variable duty cycle control method is proposed in order to compensate the weakness of conventional fixed duty cycle control method and improve the satisfaction of residents and the reduction of peak demand. The proposed method estimates the predict mean vote (PMV) at the next step with predicted temperature and humidity using the back propagation neural network model. It is possible to reduce the energy consumption by maintaining the Air-conditioner's OFF state when the PMV lies in the thermal comfort range. To verify the effectiveness of the proposed variable duty cycle control method, the case study is performed using the historical data on Sep. 7th, 2001 acquired at a classroom in Seoul and the obtained results are compared with the fixed duty cycle control method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.145-147
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• 2005

This paper presents a methodology for satisfying the thermal comfort of Indoor environment and reducing the summer peak demand power by minimizing the power consumption for an Air-conditioner within a space. KEPCO(Korea Electric Power Corporation) use the fixed duty cycle control method regardless of the indoor thermal environment. This method has disadvantages that energy saying depends on the set-point value of the Air-Conditioner and DLC has no net effects on Air-conditioners if the appliance has a lower operating cycle than the fixed duty cycle. A variable duty cycle estimates the PMV(Predict Mean Vote) at the next step with a predicted temperature and humidity coming from the back propagation neural network model. It is possible to reduce the energy consumption by maintaining the Air-conditioner's OFF state when the PMV lies in the thermal comfort range. The proposed methodology uses the historical real data of Sep. 7th, 2001 from a classroom in seoul to verify the effectiveness of the variable duty cycle method comparing with fixed duty cycle. The result shows that the variable duty cycle reduces the peak demand to 2.6times more than fixed duty cycle and increases the load control ratio by 8% more. Based on the variable duty cycle control algorithm, the effectiveness of DLC is much more improved as compared with the fixed duty cycle.

• 대한기계학회논문집A
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• 제38권9호
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• pp.979-988
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• 2014

자동차를 이용하는 시간이 늘어남에 따라 자동차 실내의 온열쾌적성에 대한 관심이 급증하고 있다. 그러나 아직까진 실제 자동차 중에서 공조시스템의 냉방성능은 자동차 제조사별로 온열쾌적성 지표를 통해 평가되지 않고, 실내의 공기 속도와 온도 등 열환경 기준에 의해 평가되고 있다. 또한 차 실내의 온열쾌적성을 수치해석으로 평가하는 경우 타당한 결과를 도출할 수 있는 수치기법에 대한 기준이 확립되지 않은 상황이다. 본 연구에서는 외부 열원을 모사하기 위하여 태양광선 추적모델을 사용하고, 공조시스템 작동 후 20 분까지 다양한 매개변수(공조시스템의 작동모드와 작동풍량, 인체모델 탑승조건)에 대한 자동차 실내의 온열쾌적성 평가를 수행하였다. 이를 통해 자동차 실내의 온열쾌적성 지표를 예측할 수 있는 평가모델을 도출하였다.