Ventilation Study and Manufacture
Poor ventilation and low air flow were highlighted as issues. Investigation showed significant build up of tunnel dust, hair and fluff on the security mesh built into the saloon vents. This was blocking air flow into the saloon. A cleaned vent showed an air flow improvement to over 140%
A direct replacement for the current vent with no additional modifications to the train. The design will reduce the collection of dust, hair and fluff by removing the security mesh while still preventing objects, particularly paper, from being pushed into the vent. The shape of the fins will be optimized with regards to air flow rate. It is also beneficial to increase the air flow around the passenger’s head and shoulders, however it is not desirable to blow the air directly onto them which can cause discomfort.
The design produced used extruded fins creating a Labyrinth which air and dust could easily pass through but any object would be stopped. Computational Fluid Dynamics software was used to calculate the air flow. Air flow around the seating and standing passengers was increased without being directed towards the passenger. On train tests showed an average air speed 5cm from the vent of 2.21 m/s, this is an increase of 1.21m/s from a datum as found carriage of 1.00 m/s. For the Central Line and Waterloo & City, 7100 vent units were produced by Creactive Design and delivery on time. Completion date 03/02/16