Thermal Science 2016 Volume 20, Issue suppl. 5, Pages: 1435-1447
https://doi.org/10.2298/TSCI16S5435B
Full text ( 1063 KB)
Cited by
Performance of low-pressure fans operating with hot air
Bogdanović-Jovanović Jasmina B. (Faculty of Mechanical Engineering, Nis)
Milenković Dragica R. (Faculty of Mechanical Engineering, Nis)
Spasić Živan T. (Faculty of Mechanical Engineering, Nis)
Svrkota Dragan M. (Jaroslav Cerni Institute for the Development of Water Resources, Belgrade)
Performance characteristics of fans are generally provided for the normal
temperature and pressure conditions (tI = 20°C, pI = 101.325 kPa, ρ I = 1.2
kg/m3). Very often, fans operate in different air conditions, occasionally at
different air temperatures. In these cases, equations obtained by the law of
similarity are usually used for recalculation of the fan operating
parameters. Increasing the inlet air temperature causes a decrease in the
characteristic of Reynolds number, and may lead to efficiency lowering of the
fan. There are also some empirical formulas for recalculation of fan
efficiency, when operating at different air temperatures. In this paper, the
common way for obtaining fan performance for different operating conditions
(air temperature changing) is presented. The results, obtained by
recalculation of fan parameters using a law of similarity, are compared to
numerical simulation results of the axial-flow fan operating with different
air temperatures. These results are compared with results obtained by some
recommended empirical formulas, as well. This paperwork is limited to
low-pressure and mid-pressure fans, which represents the majority of all fans
used in practice, for different purposes.
Keywords: low pressure and medium pressure fans, performance characteristics, air temperature, energy efficiency