Laser Displacement Sensor

A laser displacement sensor is used to correct the hot-wire position for the diverging tunnel walls. The traverse direction is not parallel with the tunnel centerline, and as such the distance normal to the surface changes with movement in the streamwise direction. To correct for this and to avoid collisions with the wall, the laser displacement sensor is used to calibrate the hot-wire position along the model span.

The Sensor

The displacement sensor used is the Laser Micro Epsilon optoNCDT 1710 and is mounted on the Y-direction traverse arm.

The sensor is connected to channel AI7 on the BNC-2120 card as shown in the wind tunnel connections.