October 23-27, 2023

The large aeroelastic model AE2 has been tested at POLIMI’s Large Wind tunnel under gust excitation. The model, representative of the U-HARWARD project Reference Aircraft with Aspect Ratio = 15, implements the Folding WingTip configuration, i.e. the outer 30% of the wing is connected to the central wing by means of a hinge remotely controlled. The device allows to switch from the fixed to the free configuration, with a pre-defined delay with respect to the incoming gust. The half model, installed in a vertical position, is trimmed by means of a long stroke electrodynamic actuator (WAS system) located below the dummy floor installed in the testing room, able to generate a dummy weight. Eight cameras positioned on the vertical wall of the chamber allow to identify in real time the displacement of several markers installed on the model. Accelerometers and strain gauges allow to measure local accelerations and internal forces along the wing spar. In about 3 days of testing more about 180 1-cos gust profile have been investigated playing with the time delay between the impacting gust and the hinge release mechanism to assess the potential impact on gust loads.

In the short video below, you can recognize the different test phases:

In this video you can see different phases:

  • Model trimmed by pitch control at selected flight test point (n=1), waiting for the gust (back camera)
  • Gust impact, and release of the FWT mechanism (back camera)
  • Same steps viewed from the front camera.
  • Pitching operation to remotely re-engage the hinge mechanism.
  • Re-trim of the model waiting for next gust.
  • The same test captured in real time using the photogrammetry system (6 cameras) installed in the testing room.