• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.324-332
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• 2017

The comparative experiments were conducted for single span greenhouses where cucumbers were cultivated to analyze the effect of heating between a carbon fiber electric heating element heater and an oil hot air heater in terms of the inside climate, energy consumption and plant growth. In order to analyze the effect of heating capacity, 6, 9, and 16 kW of electric powers were supplied to the electric heating element for same setting temperature of 15?. As a result, as the heating capacity increased, the number of ON-OFF cycles of the electric heating element and the temperature inside the greenhouse increased proportionally. In the comparison of two heaters, it was shown that the temperature and relative humidity distributions of the electric heating element installed greenhouse was much uniform than those of the oil hot air heater installed greenhouse. The heating energy consumptions during the heating period of 79 days were 867L for the oil hot air heater and 8,959 kWh for the electric heating element heater, and the heating costs were 607 and 403 thousand won respectively. In the electric heating element installed greenhouse, the cucumber growth was slightly better and the yield was 4.3% higher than those of the oil hot air heater installed greenhouse, but there were no statically significant difference in the cucumber growth and yield between greenhouses.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.313-319
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• 1999

간접열식 LPG온풍난방기는 LP(Liquefied Petroleum)가스를 열원으로 한 온풍난방기를 말한다. LP가스는 프로판(Propane, $C_3$H$_{8}$)과 부탄(Butane, $C_4$H$_{10}$)을 주성분으로 하는 혼합물로 에탄, 프로필렌, 부틸렌 등이 약간 포함되어 있는 기체로 액화 및 기화가 쉬우며 기체상태에서는 비중이 공기보다 무겁고 액체상태에서는 물보다 가볍다. 또한, 기화할 때는 다량의 열과 연소시 많은 공기를 필요로 하고 온도에 따라 액체의 부피가 변하는 특성을 가지고 있으며 무색, 무취, 무독하다. LP가스의 발열량은 12,000kcal/kg으로 경유나 보일러등유 보다 약 30% 정도 높아 난방연료로서의 사용 및 취급성이 우수하다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.04a
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• pp.9-14
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• 1999

1. LPG 온풍기는 용량 16$\times$$10^4$ ㎉ 건타입가스버너, 연소부 및 열교환부, 6개의 50kgLPG탱크와 자동절체기, 가스메타, 배관으로 구성하였다. LPG 온풍기의 이론연소효율은 91%, $CO_2$ 배출량은 11.74%, CO배출량은 0ppm, 과잉공기비는 1.16, 배기가스온도는 253$^{\circ}C$, 온풍온도는 8$0^{\circ}C$로서 우수한 성능으로 나타났다. 2. LPG온풍기에서 배출되는 배기가스중의 $CO_2$ 를 온실로 공급하기 위하여 $CO_2$ 공급기를 제작하여 배출가스연도에 부착하였다. $CO_2$ 공급기는 흡입형 시로코팬(1200㎥/h)과 차단문으로 이루어졌다. 1-2W형 300평 온실내의 $CO_2$ 농도를 1000ppm으로 올리기 위해서는 $CO_2$ 공급기를 약 1시간 정도 운전시켜야 할 것으로 판단되었다. 3. LPG온풍기와 경유온풍기의 경제성 비교분석에 의하면 현 시점의 경유 가격 242원, LP가스 가격 435원을 기준으로 연간소요비용은 각각 5,392,430원, 5,299,917원으로 경유온풍기가 10만원 정도 경제적이지만 탄산가스 시용비용, 탄산가스 공급으로 인한 작물의 수량증대 및 고품질 생산물을 고려한다면 LPG온풍기 사용이 더 경제적이라 사료된다.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.3
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• pp.107-111
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• 2011

This carbon nano heating system was consisted of power supply equipment, a carbon fiber and a stainless flexible hose. carbon nano heating system was manufactured by carbon fiber of a power capacity 30kw/h and light-oil hot air heater in control plot was the heating capacity 30,000kcal/h, As the result, Temperature difference due to carbon nano heating system and hot air heater in greenhouse showed that air temperature at experimental greenhouse, comparison greenhouse were $14.8^{\circ}C$, $13.4^{\circ}C$ respectively. It was found that carbon nano heating system and light-oil hot air heater heating cost were 1,095,740won, 2,683,628won. therefore as heating cost saving 60%. Yield of tomatoes cultured in greenhouse using carbon nano heating pipe was 4% inclease. Economic analysis comparison between the carbon nano heating pipe and the hot air heater in greenhouse were 41% respectively.