Naslov
Investigation on thermal performance of electric heaters with nanofluids

Autori
Zheng, Dan ; Zhai, Zhengjia ; Wang, Wei ; Wang, Jin ; Vujanović, Milan ; Sundén, Bengt

Izvornik
Fuel (Guildford) (0016-2361) 320 (2022); 123966, 12

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Electric heater ; Ferrofluid ; Heating efficiency ; Magnetic field ; Nanofluid

Sažetak
This work aims to analyze thermal performance for an electric heater filled with different nanofluids, including SiO2-water nanofluid, Fe3O4- water nanofluid, and Cu-water nanofluid. The effect of nanoparticle concentration (0.1–2.0 wt%) is also discussed. Results indicate that Cu-water nanofluids show better heat transfer performance than the other nanofluids. The highest heating efficiency for the external environment is observed for Cu-water nanofluids with 2.0 wt% mass fraction. Cu nanoparticles show some shortcomings, such as high costs and easy oxidation. With action of a magnetic field, magnetic nanoparticles destroy the flow boundary layer close to the wall. Thermal performance of Fe3O4-water nanofluid under magnetic fields shows an ambient equilibrium temperature of 65.6 °C, which is 0.1 °C lower than that of Cu-water nanofluid. Although the heating time of Fe3O4-water nanofluid (108 min) is longer than that of Cu-water nanofluid, it provides an alternative material with low costs to achieve the high-efficient heating. This research provides economical and valuable methods to improve thermal performance of electric heating structures, and it is a promising way to reduce carbon emission from burning fossil fuels for heating supply in cities and villages, particularly if the electricity is from renewable resources.

Izvorni jezik
Engleski

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