Volvo

The wind-tunnel in Göteborg, Sweden is a full-scale slotted wall type. The traverse was installed in 1985. The main part of the traverse is applied to the wind, and the shape is therefore streamlined. The blockage of the system has been minimised to achieve minimum flow disturbance.

The main beams has the girder on the top, this is to avoid blockage of the slots in the ceiling. Cables for servos and for instrumentation are guided inside the construction. The instrument cables are accessible at the lowest part of the vertical arm.

The traverse is guided in the wind direction by the rails above the ceiling level and located in the two corner slots. The parrallel control of the left and right side are achieved by a electronic "master slave" function. The system has 4 servo units to move along the x-axis, 2 servo units to move along the y-axis and one servo unit to move the vertical arm.

The traverse has a parking position in the diffuser, this to minimize the influence from the traverse when not in use.
To achive a parking positioning as close to the ceiling as possible the rails from the test section to the parking positioning in the diffuser are inclined.
The precision rails do not allow for such inclination, why the system changes between two rails systems when traveling in the parking positioning.