Wind tunnel measurements of two-dimensional wing sections, or airfoils, are the building\nblock of aerodynamic predictions for many aerodynamic applications. In these experiments, the forces\nand pitching moment on the airfoil are measured as a function of the orientation of the airfoil relative\nto the incoming airflow. Small changes in this angle (called the angle of attack) can create\nsignificant changes in the forces and moments, so accurately measuring the angle of attack is critical\nin these experiments. This work describes the implementation of laser displacement sensors in a\nwind tunnel; the sensors measured the distance between the wind tunnel walls and the airfoil, which\nwas then used to calculate the model position. The uncertainty in the measured laser distances, based\non the sensor resolution and temperature drift, is comparable to the uncertainty in traditional linear\nencoder measurements. Distances from multiple sensors showed small, but statistically significant,\namounts of model deflection and rotation that would otherwise not have been detected, allowing for\nan improved angle of attack measurement.
Loading....