Its improtant for any tunnel operators to lower the costs and improve energy efficiency, especially on cost consuming technical facilities as Ventilation systems. The reversible MoJet^® tunnel ventilation system typically enhances by 25% the in-tunnel aerodynamic thrust compare to other jet fans.

Longitudinal tunnel ventilation systems provide air flow along the length of tunnel, to satisfy air quality requirements and to control smoke in case of a fire in the tunnel. 

The MoJet^® fans from Systemair improve efficiency of tunnel ventilation systems by minimising the Coanda effect. The Coanda effect refers to air steam produced by each jet fan and the effect to be drawn to nearby walls, leading to increased friction and increasing energy required to move the air through the tunnel. A special design reduces this effect. The MoJet^® uses shaped nozzles which turn the airstream away from the tunnel ceiling and walls.

In addition using motors with a lower rotational speed, achieves the required aerodynamic thrust while, at the same time, in many cases fan-generated noise can be minimised, says Systemair.

By using the newest technology available its possible to reduce number of jet fans, reduce power, reduce cabling cost, reduce electrical facilities cost and a achieve significant reduction of operational cost. 

Weblinks: https://www.systemair.com/Global/Solutions/Tunnel-and-Metro/Road-Tunnel/