• 설비공학논문집
• /
• 제16권11호
• /
• pp.1068-1076
• /
• 2004

Technology on the proportional integral (PI) control have grown rapidly owing to the needs for the robust capacity of the controllers from industrial building sectors. However, PI controller requires tuning of gains for optimal control when the outside weather condition changes. The present study presents the possibility of reinforcement learning (RL) control algorithm with PI controller adapted in the HVAC system. The optimal design criteria of RL controller was proposed in the Environment Chamber experiment and a theoretical analysis was also conducted using TRNSYS program.

• 설비공학논문집
• /
• 제15권9호
• /
• pp.751-761
• /
• 2003

We performed the numerical analysis on the airflow characteristics in the two type of cleanroom systems, which are the axial fan type (AFT) and the fan filter unit (FFU). A computational fluid dynamic model was applied to investigate and compare the nonuniformity, the deflection angle and the air ventilation effectiveness of the two designs of cleanrooms when dampers are adjusted and not adjusted. And the flow-resistance models of the various components were used in this simulation. We know that the airflow characteristics of the cleanrooms are largely affected by damper adjusting And we also find out that the FFU system is superior to the AFT system through the comparison of the cleanroom performance indices.

• 설비공학논문집
• /
• 제13권11호
• /
• pp.1072-1078
• /
• 2001

The real time optimal control algorithm of the DDC controller for chilled water and supply air temperature set-point of heating, ventilating, air-conditioning and refrigeration systems has been researched for minimization of the total power which is consumed by the chiller, chilled water pump and air handing unit fan. The study has been done by using TRNSYS program in order to analyze the central cooling system in terms of the environmental variables such as indoor cooling lead and wet-bulb temperature. This optimal control alogorithm saves more energy and is suitable for real time on-line control in comparison with conventional method.

• 설비공학논문집
• /
• 제4권1호
• /
• pp.1-10
• /
• 1992

The purpose of this paper is to provide an efficient method of operating and designing HVAC systems for reasonable energy consumption in building. Accroding to the conditions of indoor temperature and humidity, and the methods of dividing and grouping the capacity of boiler and refrigerator, the amount of their annual energy consumptions is simulated by using an energy analysis program which is developed in this paper, and opatimal design methods of HVAC system are suggested as well.

• 설비공학논문집
• /
• 제19권1호
• /
• pp.36-42
• /
• 2007

The latest cars give much importance in the role of HVAC system that controls the environment of the area for passengers more than just basic capability In this study, we drew the automobile interior as three dimension and arranged a method of numerical analysis on HVAC environment in the automobile interior displaying air current distribution and temperature distribution through simulation of the automobile interior on the ventilation volume and outlet area, The aim of this study is to develop the estimated method for HVAC environment in the automobile interior. Results of numerical analysis, to cool automobile interior needs more considerations if thinking cheerful surroundings of automobile interior air but the more magnitude of outlet is small, the more cooling capability is excellent and realistic countermeasures about a realistic geometry and boundary condition.

• 설비공학논문집
• /
• 제21권2호
• /
• pp.87-93
• /
• 2009

Slim telecommunication cabinet cooler, equipped with parallel flow heat exchangers and operating with R-22, is developed. The performance is compared with imported one, equipped with fin-tube heat exchangers and operating with R-134a. Test results show that the newly-developed cooler increases the cooling capacity by 6% and EER by 33%. The refrigerant charge for the developed cooler is 500g compared with 1250g for the imported one. The adoption of parallel flow heat exchanger appears to have reduced the refrigerant charge. In addition, it is shown that the reduced air flow rates through parallel heat exchangers as compared with those through fin-tube heat exchangers are beneficial to the reduction of the equipment noise.

• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2005년도 학술대회 논문집
• /
• pp.225-231
• /
• 2005

본 연구에서는 프랜트 및 빌딩자동제어 분야에서 적용이 확대되고 있는 LonWorks 필드버스를 이용하여 기존의 공기조화 시스템를 제어하고 있는 DDC제어기를 대체할 수 있도록 필드버스에서 사용이 가능한 고성능 저가의 지능형 제어모듈을 개발하였다. 이는 필드버스 기반의 AHU 전용 지능형제어기를 새로운 설계기술로 개발하고 상품화를 실현하였다. 특히 S/W부분에서도 8 bit Neuron chip에 매우 콤팩트하게 내재된 고성능 응용프로그램도 개발하였다. 또한 Echelon 사의 iLON 100 server의 Soap/XML을 사용하여 Web 브라우저에서 쉽게 프로그램을 작성 제어모니터링 기법을 개발하였다. 공조기의 실험시스템을 구축하여 개발된 전용 제어기 및 Web 기반제어를 실험한 결과 밸브, 댐퍼제어 및 감시기능이 기존 DDC 제어기보다 우수함을 확인하였으며 원격제어 기반을 구축하였다.

• 한국정보통신설비학회:학술대회논문집
• /
• 한국정보통신설비학회 2008년도 정보통신설비 학술대회
• /
• pp.482-485
• /
• 2008

통신기기실은 겨울철에도 냉방이 이루어질 만큼 열이 많이 발생하는 공간으로, 다수의 특수형 공조기가 설치되어 운용되고 있는데, 여기서 발생된 열은 열교환을 통하여 실외 기에서 그냥 외부로 버려지고 있다. 이 열은 겨울철에 사무실 난방과 온수공급에 필요한 적당한 온도와 풍부한 열량을 가지고 있어 그동안 활용 방법을 많이 모색해 왔으나, 시도되었던 제품이나 방법은 현실성이 떨어지거나 제품화 되지 못하고 있는 실정이었다. 이에, KT인프라연구소에서는 현실성 있는 제안으로 실외기로 가는 고온 고압의 냉매를 인접 사무실로 자동 전환시켜 난방을 가능케 하는 Package Type의 응축열 난방기를 개발하였는데, 본 논문에서는 이에 대한 개발과정과 Spec을 소개하고, 철저한 성능검증과 에너지 절감 효과 분석 결과를 제시하여 사업 적용에 필요한 기초자료로 활용 할 수 있도록 하였다. 개발된 응축열 난방기는 에너지를 대폭 절감할 수 있을 뿐 아니라 지구 온난화의 주범인 $CO_2$를 감축시킬 수 있어 대외 이미지 개선에도 크게 기여할 것이라고 생각된다.

• 설비공학논문집
• /
• 제12권3호
• /
• pp.302-308
• /
• 2000

The major source of noise in air-conditioner is a compressor. Therefore, noise reduction in a compressor is quite significant as an element technology in air-conditioner field. Recently, a scroll compressor is widely used, because a scroll compressor features lower noise, due to less pulsation of gas pressure, than that of the rotary compressor. During a past noise reduction effort on a scroll compressor, noise radiation from the discharge portion of the hermetic shell was identified as the major contributor to overall noise. For a reduction of noise, the source of noise at the discharge portion must be identified. This paper presents detailed analyzes for the discharge pressure pulsation and cavity resonance at discharge space, which will make possible a low noise design of a scroll compressor.

• 설비공학논문집
• /
• 제15권11호
• /
• pp.970-978
• /
• 2003

This paper aims at suggesting design guidelines for a perimeter-less HVAC system that contributes energy savings. Perimeter-less HVAC system is one that relieves difficulties such as handling mixing loss, uneven radiative environment, and maintenance and repair. It prevents heat load gained through window and outdoor wall without modifying a previously equipped building skin system. In this paper, we conducted a large-scale model experiment to see how the push-pull air flow would handle indoor heat to obtain an optimized perimeter-less design, and then we plan to perform several kinds of CFD (computational fluid dynamics) cases through numerical simulation