Energy-efficient tunnel ventilation device

Abstract

A ventilation device that enhances the effective longitudinal thrust of a fan assembly installed within a tunnel, by turning the discharged flow away from the surrounding tunnel surfaces and tilting the nozzle trailing edge ( 6 ) so that it forms an angle ( 16 ) to the nozzle centreline ( 8 ).

1 . A fan assembly for installation in a tunnel to provide ventilation in the tunnel, the fan assembly comprising:
 a fan rotor for generating a ventilating flow; and   the inflow into the fan rotor being substantially parallel to the outflow from the fan rotor; and   a nozzle coupled to the fan, the nozzle having a trailing edge at the distal end from the fan; and   the assembly being arrangeable such that a ventilating flow generated by the fan will pass through the nozzle before exiting the assembly to enter a tunnel to be ventilated; and   the nozzle shape being arranged to turn the flow away from the surrounding tunnel surfaces, in that at least one edge of the nozzle throughbore is at an angle to the fan centreline; and   wherein the angle made between the nozzle trailing edge and the centerline of the nozzle is within the range of 45 degrees to 85 degrees.   
     
     
         2 . A fan assembly with a nozzle as described in  claim 1 , wherein the nozzle trailing edge forms the shape of a circle. 
     
     
         3 . A fan assembly with a nozzle as described in  claim 1 , wherein at least one edge of the nozzle throughbore is parallel to the fan centreline. 
     
     
         4 . A fan assembly with a nozzle as described in  claim 1 , wherein a bellmouth is attached to the nozzle edge. 
     
     
         5 . A fan assembly with two nozzles as described in  claim 1 , with one nozzle installed on each side of a fan. 
     
     
         6 - 8 . (canceled)