In road tunnels, ventilation systems are essential to ensure air quality and the safety of road users.
These systems are designed to remove smoke, fumes and other pollutants in the event of a fire or accident. The type of fans used in road tunnels can vary depending on the specific requirements and the length of the tunnel. The design and choice of ventilation system is determined by several factors, including the length of the tunnel, the expected traffic volume, the maximum traffic speed, the risk of accidents, and local regulations and safety standards. Existing tunnels also need to be adapted to new safety standards. The design and adaptation of an existing situation is in most cases a determining factor. Each project may have unique requirements that affect ventilation needs. Therefore, tunnel ventilation systems are usually carefully designed and evaluated to ensure the best performance and safety.
The following types of fans are used by Zitron in road and railway tunnels:
These fans are fitted with aerodynamically optimised blades to achieve high efficiency. They can be supplied with or without adjustable blades.
Partially reversible fans
These fans are equipped with aerodynamically well-profiled blades, allowing good efficiency in the normal direction of rotation or blade angle. Reversibility can be achieved by changing the direction of rotation of the fan or by changing the blade angle.
Fully reversible fans
These fans are equipped with symmetrically profiled blades that have a high efficiency. Reversibility can be achieved by changing the direction of rotation of a fixed pitch fan. Or by changing the blade angle of a variable pitch fan.
All these types of fans can be designed, tested and certified for high temperatures according to ISO EN 12101-03.
Reversible jet fans
The symmetrical shape of the blades ensures almost identical thrust in both directions of rotation.
Unidirectional jet fans
The aerodynamically profiled blade shape gives a very good thrust to power ratio.
All these fan types are designed, tested and certified for high temperatures according to ISO EN 12101-03.
The design of all types of jet fans can be optimised for sound power, thrust or power consumption.
Overpressure fans in road tunnel escape routes are used to maintain a safe environment in the event of an emergency such as a fire. The main function of these fans is to create and maintain an overpressure in the tunnel escape routes.