Abstract: The article is about the possibility of applying nanofluids in heat supply systems as a coolant. The most effective nanofluids were selected by analyzing the thermal conductivity, concentration, size, mass, and velocity of nanoparticles. It is presented the dependences of the heat transfer coefficient of a nanofluid on the Reynolds number and the heat transfer coefficient on the volume concentration. According to calculations, with the addition of 1% vol. of nanotubes to the coolant path that gives heat in the evaporating section of the heat pump, the heat transfer coefficient of a nanofluid increases by 100%.
Keywords: nanofluid, nanoparticles, heat supply system.
The use of nanofluids in heating and ventilation systems can give a significant increase in heat transfer.
For the use of nanofluids as a coolant it is necessary to have the knowledge of their thermophysical properties. For this purpose we have worked on analysis of nanoliquids researches.
In works [1, 3, 4] on the study of heat transfer in nanofluids it is demonstrated heat conductivity of suspensions of ultradisperse oxides of aluminum, silicon and titanium in water at volume concentration about several percent, exceeds the thermal conductivity of pure liquid by tens of percent.
Results of experiment with nanoparticles of various size show that heat conductivity of liquid on the basis of larger particles is rather well de-scribed by theory of Maxwell [2].
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Velkin VI, Shkolniy AV, Kirillov MP, Achkeev MV: Swirler, RUS 69942; 16.07.2007.