69cf3305_bstracts___IEEE_GreenTech_2013__Category____Sub_Category
[Paper Title, Abstract] A Model of Natural Circulation Solar Water Heater Using CO2 as Working Fluid Show AbstractHide Abstract Theoretical and experimental study of a natural circulation solar water heater using R744 as mediating fluid is presented. Solar collector consists of nine parallel aluminum foil enveloped copper U tubes were suspended in evacuated glass tubes. U shape bent copper tubes were connected through stainless steel headers to heat exchanger. The shell-and-coil counter flow heat exchanger was designed, fabricated and tested using CO2 refrigerant material. The helical coil copper tube was immersed in bulk water tank. Hot CO2 was piped to upper coil baffle for circulation through counter flowing water to lower baffle. Water input/output pipes were inserted from the top and copper coil tubes from upper and lower sides of water tank. Evacuated glass tubes solar collector increased CO2 refrigerant temperature from 35 to 78C giving temperature difference of 43C. The CO2 temperature at exit from heat exchanger was measured to be 40C at ambient air temperature of 36C. Solar heat transfer raised the inlet water temperature from 26 to 55C under off water tap condition in about three hours. Water temperature difference between inlet and outlet ports of heat exchanger was measured to be 27C. Heat capacity increases manifolds at critical point, therefore, natural circulation solar water heater performance can further increase if the system is used in mild sunshine cold weather regions. [Schedule] TPD-SEH1 [Category :: Sub-Category] 
Solar – PV
Abstracts « IEEE GreenTech 2013
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