THEORETICAL STUDY OF THE USE OF NANOFLUIDS FOR WATER HEATING IN FLAT-PLATE COLLECTORS
DOI:
https://doi.org/10.59627/cbens.2008.1375Keywords:
Solar Energy, Flat-plate collector, Nanofluid, Alternative EnergyAbstract
This paper presents a computational simulation of a flat-plate collector that operates with a nanofluid as a heat transfer fluid from the flat-plate to the water in the reservoir. Nanofluids are composed of a mixture of a base fluid and nanoparticles of metals or metal oxides, aiming to improve some termophysical properties of the base fluid. In this work, it was used solar data from 16/12 to 22/12 and 16/06 to 22/06 of 2005 from the city of Florianópolis. It was also developed a bath demand with its temperature as a function of the ambient temperature. There were used 2 nanofluids, both based on water: 0,2% of alumina and 0,1% of copper oxide. Their properties were generated from data available on the literature. Than it has been modeled in the software named Mathematica 5.2 two different heating water systems: a traditional one and the other with a pass age heat exchanger. Both operate with forced circul ation. The flat-plate is standard and the reservoir has 300 liters of capacity. The passage heat exchanger is of the coil type, in which flows the nanofluid. For performance comparison, the same system was simulated with water in the heat exchanger instead of the nanofluid. It was used as comparison parameters the temperatures in the water reservoir at the end of each day and the diary energy absorbed by the systems.
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