• Proceedings of the SAREK Conference
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• 2006.11a
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• pp.10-10
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• 2006

• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.113-113
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• 2004

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.199-199
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• 2007

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.189-189
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• 2003

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.119-119
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• 2003

• Proceedings of the SAREK Conference
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• 2004.06a
• /
• pp.245-245
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• 2004

• Proceedings of the SAREK Conference
• /
• 2003.07a
• /
• pp.188-188
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• 2003

• Proceedings of the SAREK Conference
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• 2004.06a
• /
• pp.243-243
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• 2004

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.4
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• pp.173-179
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• 2013

Middle-sized $CO_2$ water heater having compressor power of 7.45 kW was designed, and its performances were experimentally tested. Besides, optimum design of the $CO_2$ water heater was conducted by cycle simulation. When ambient temperature of $7^{\circ}C$ and hot water outlet temperature of $80^{\circ}C$ the $CO_2$ water heater showed the COP of 3.2. As hot water temperature increased the COP is getting decreased due to significant increase of compressor power consumption compared to increasing rate of heating capacity. When ambient temperature increased from $-3^{\circ}C$ to $12^{\circ}C$ the COP increased by 30%. The optimum components design of a gas cooler, an internal heat exchanger, and an evaporator were conducted, and the experimental correlation between amount of EEV opening and ambient temperature, and hot water temperature was suggested.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.1
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• pp.16-24
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• 2005

The goal of the present paper is to show the optimum design and operation conditions on 6 kW solar water heating system by using computer simulation with verified modelling. As the object functions, we took not only the amount of acquired and auxiliary heat but LCC, which has a relative importance and decisive role in economy. As expected, the maximum heat is acquired at the slope of collector with the equal degree to the latitude, facing the south. The capacity increase of the circulation pump and the storage tank lead to the increase of acquired heat and the decrease of auxiliary heat, but do not necessarily give economical advantages owing to additional electrical power consumption. In the present system, the minimum LCC can be obtained at the storage tank volume of 450 L and the mass flow rate of 0.344 kg/s.