Advances in Acoustics and Vibration / 2012 / Article / Tab 2

Research Article

The Conceptual Design of High Pressure Reversible Axial Tunnel Ventilation Fans

Table 2

Relative merits of the three fan system concepts.

Concept 1
(Counter rotating)
Concept 2
(High speed)
Concept 3
(Double ended motor)

Peak efficiency+8%+2%+5 %
Noise15 dB noisier10 dB noisier8 dB noisier
Cost2.0 a single fan2.5 a single fan2.0 a single fan
Size2.0 the length of a single fan1.1 the length of a single fan1.3 the length of single fan
Technical riskLowHighMedium

Note 1: All comparisons are relative to that of a single-stage fan of the same diameter.
Note 2: Peak efficiency is relative to that of a current state of the art single-stage reversible fan with a peak efficiency of 70%.