Fig. 1.
NASA Helios [11] and Arbus Zephyr Solar High Altitude Platform System [5].
Fig. 2.
Diagram of two-way fluid-structure interaction implemented in XAVEL (from [28]).
Fig. 3.
Different levels of structure modelling.
Table 1.
| Code Class | General Type | Brief Description |
|---|---|---|
| F1A | Gliders (A2 ‘Nordic’) |
|
Fig. 4.
Sketches of the jig shape of the solar UAV under analysis. Dihedral angle: 0 deg, −3 deg.
Fig. 5.
The shape of the MOD-42 airfoil with a flat-upper surface, adopted from [40].
Table 2.
Wing geometry parameters.
| Parameter | Value |
|---|---|
| Span [m] | 3 |
| Reference area [m2] | 0.51 |
| Aspect ratio | 17.65 |
| Mean aerodynamic chord [m] | 0.17 |
Fig. 6.
Explanation of The D-Box build technology.
Fig. 7.
Uniform structure of the wing along the span.
Table 3.
Flight conditions under analysis and required lift coefficient.
| Altitude [km] | Air Density [kg/m3] | Speed [m/s] | Design total lift [N] | Angle of attack [deg] | Coefficient of Lift |
|---|---|---|---|---|---|
| 20 | 0.089 | 18 | 4,9 | 4 | 0.67 |
Fig. 8.
Average wind speeds in m/s vs. altitude in km (figure adapted from [41]).
Fig. 9.
Lift coefficient vs angle of attack: comparison XAVEL and wind tunnel test (WTT) (from [27]).
Fig. 10.
Geometry normalized deflection of wing at 8 m/s at sea level.
Fig. 11.
Wing geometry at 18 m/s at 20 km for different angles of attack: Deflection (A) and Angle of inclination (B).