• 월간 기계설비
• /
• 통권24호
• /
• pp.100-102
• /
• 1992

• 월간 기계설비
• /
• 통권227호
• /
• pp.89-92
• /
• 2009

설비건설업을 하다보면 여러 가지 자재들을 사용해야 한다. 하지만 비슷한 제품이 많아 우리가 시공하는 현장에 어떤 제품이 적합한 것인지 궁금할 때가 많다. 더욱이 제품 특징 등을 알고 싶을 때 일일이 찾아봐야 하는 번거로움이 따른다. 본지는 회원사의 설비자재에 대한 궁금증을 해소하기 위해 지난 2007년 6월호부터 특정 자재를 선정하여 제품의 특징 용도 등을 담은 '자재의 모든 것'을 게재한다.

• KIEAE Journal
• /
• 제12권4호
• /
• pp.89-95
• /
• 2012

At present, many countries are trying to reduce green gas emissions to mitigate the effects of these gases on climate change. Year after year, there have been efforts to cut energy use for heating and cooling. Heating and cooling systems, common in all forms of housing, are increasing due to the constant supply of new housing resulting from improvements in economic growth and the quality of life. Thus, studies related to the design of cooling and heating systems to improve energy efficiency are expanding. Among the new designs, radiant floor cooling and heating systems which use capillary tubes are becoming viable means of reducing energy use. Radiant floor cooling and heating systems which use capillary tubes are creative and sustainable systems in which cool and hot water is circulated into capillary tube which has small diameter. In this study, the cooling and heating performance of this type of capillary tube system is investigated in an experimental study and a simulation using TRNSYS. The results of the experimental study show that under a peak load, a capillary tube radiant floor cooling system using geothermal energy can achieve desired indoor temperature without an additional heat source. The set room air temperature is maintained while the floor surface temperature, PMV and PPD remain within the comfort range. Also, this system is more economic than a packaged air conditioner system due to its higher COP. The results of the simulation show that the capillary tube radiant floor heating system maintains set temperature more stable than a PB pipe radiant floor heating system due to its lower supply temperature of hot water. In terms of energy consumption, the capillary tube radiant floor heating system is more efficient than the PB pipe radiant floor heating system.

• 대한지하수환경학회지
• /
• 제4권3호
• /
• pp.116-121
• /
• 1997

정화 효율과 운영상의 문제점을 파악하였다. 반응조 유입수 및 방류수에 대하여 현장에서 pH 및 Eh(산화환원전위)를 측정하였고 Cd, Pb, As, Zn, Cu, Fe, Al 및 Mn 등을 실험실에서 분석 하였다. 반응조 방류수에 대한 수질분석 결과 우분 및 석회석이 섞인 볏짚 반응조의 Cu, Zn, Fe, Cd, Al, Mn및 Pb의 정화효율(최대)은 98%, 100%, 99%, 100%, 97%, 61% 및 100%였고 이때 반응조의 수질환경은 pH 6 그리고 Eh 값이 -300 mV부근의 환원환경이었다. 그러나 시간이 경과함에 따라 Eh 값은 상승하였고 Al을 제외한 금속성분의 정화효율도 낮아져 반응조의 혐기환경유지는 금속성분의 정화에 매우 중요하였다. 반응조 시설을 운영한 결과 배관내의 산화물 Scale 및 기질물질의 부피 변화는 광산배수의 흐름을 방해하는 요소로 나타났다.

• 설비공학논문집
• /
• 제30권2호
• /
• pp.68-82
• /
• 2018

Radiant floor heating systems with capillary tubes are energy saving systems in which hot water is circulated into capillary tube with a small diameter. In this study, the heating performance of capillary tube system is investigated in an experimental study and a simulation model. The results of the study showed that, the capillary tube radiant floor heating system maintains a more stable floor surface temperature in comparison a PB pipe system. In terms of energy consumption, the capillary tube radiant floor heating system proved to be more efficient than the PB pipe heating system at $40^{\circ}C$ of low temperature hot water supply. The difference between water temperature and room temperature can be held low for heating which saves energy. Low temperature radiant floor heating system with capillary tubes have significant advantages such as health improvement, low energy cost, optimum use of heat source(boiler) and higher operational efficiency.

• 설비공학논문집
• /
• 제18권1호
• /
• pp.17-23
• /
• 2006

This study is to investigate the pressure wave characteristics and the maximum pressure rise generated by instantaneous valve closure at the end of the straightening polybutylene piping system. Experiments were conducted under the following conditions: initial pressure $1\~5$ bar, flow velocity $\~0.5-3.0m/s$ and water temperature $25^{\circ}C$. Results indicated that the peak pressure generated by quick valve closure reached Joukowsky's value. We also found that the maximum pressure rise and the pressure history depended on not only initial steady pressure but also flow velocity.

• KIEAE Journal
• /
• 제14권4호
• /
• pp.119-125
• /
• 2014

This study investigated the effects of pipe network materials and distance on system performance utilizing unused energy sources in large-scale horticulture facility. For this, the modeling was performed with a 100 m long and 100 m wide rectangular shaped glass house having an area of 1ha ($10,000m^2$) using EnergyPlus software. The heat sources considered were air source, geothermal heat, power plant waste heat, sea water heat, and river water. The temperature variation of the fluid with regard to pipe material and distance from the heat source and the resultant heat pump electricity consumptions were calculated. It turned out that the fluid temperature reaching the heat pump increased as the distance from the heat source increased in case of sea water and river water, which have higher temperatures than the surrounding soil, improving the heat pump efficiency. It was vice versa in case of the power plant waste heat. In addition, pipe material of PVC showed the smallest effect on the system performance variation due to the lowest thermal conductivity, compared to PB and HDPE.