Reference models
The model that opens when using the default onshore template is the well known NREL 5-MW wind turbine. This section shows how to modify the default template to obtain two other widely used reference wind turbines, the DTU 10-MW wind turbine and the IEA 15-MW wind turbine
You can find
You can find
- the NREL 5-MW wind turbine, defined in Jonkman et al. (2009k), here https://www.nrel.gov/docs/fy09osti/38060.pdf
- the DTU 10-MW wind turbine, defined in Bak et al. (2013), here https://rwt.windenergy.dtu.dk/dtu10mw/dtu-10mw-rwt (last accessed February 2021)
- the IEA 15-MW wind turbine, defined in Gaertner et al. (2020), here https://github.com/IEAWindTask37/IEA-15-240-RWT (last accessed February 2021)
Note: several definitions of the blades can be found (for example blades made in order software). These definitions are supposed to be equivalent, but small discrepancies can occur. To ensure that our blade definitions are correct, we run verification tests that you can find in the Benchmarking tests. The detailed definition of the blades in Ashes is also provided in the DTU 10-MW and IEA 15-MW documents.
The parameters that need to be modified to go from the NREL 5-MW turbine to the DTU 10-MW turbine are given in the following table:
| Part | Parameter | NREL 5-MW | DTU 10-MW | IEA 15-MW |
| Wind turbine | Controller path | - | \DLL Controllers\BasicDTUController\BasicDTUController.dll | \DLL Controllers\ROSCO\ROSCO.dll |
| Wind turbine | Input file argument | - | - | IEA15MW.IN |
| Wind turbine->RNA | Generator | Variable speed | Bladed DLL | Bladed DLL |
| Wind turbine->RNA | Transmission | Geared | Geared | Direct drive |
| Wind turbine->RNA | Demanded pitch | PID | Bladed DLL | Bladed DLL |
| Wind turbine->RNA | Tilt angle | 5 | 5 | 6 |
| Wind turbine->RNA->Rotor | Blade | NREL 5-MW | DTU 10-MW | IEA 15-MW |
| Wind turbine->RNA->Rotor | Cone angle | 2.5 | 2.5 | 4 |
| Wind turbine->RNA->Rotor->Hub | Radius | 1.5 m | 2.8 m | 3.97 m |
| Wind turbine->RNA->Rotor->Hub | Mass | From radius | 105 520 kg | 190 000 kg |
| Wind turbine->RNA->Main shaft | Hori. distance to hub | 5 m | 7.1 m | 10.604 m |
| Wind turbine->RNA->Main shaft | Vert. distance to hub | 2.4 m | 2.75 m | 5.462 m |
| Wind turbine->RNA->Main shaft | Shaft radius | 0.8 m | 1 m | 1 m |
| Wind turbine->RNA->Main shaft | Wall thickness | 0.028 m | 0.049 m | 0.1 m |
| Wind turbine->RNA->Nacelle frame | Mass | 240 000 kg | 446 036 kg | 630 888 kg |
| Wind turbine->RNA->Nacelle frame | CM horizontal offset | -1.9 m | -2.687 m | 3.945 m |
| Wind turbine->RNA->Nacelle frame | CM vertical offset | 1.75 m | 2.45 m | 3.352 m |
| Wind turbine->RNA->Gearbox | Gear ratio | 97 | 50 | N/A |
| Wind turbine->RNA->Generator | Efficiency factor | 0.944 | 0.944 | 0.9655 |
| Support structure->Tubular tower | Height | 87.6 m | 115.63 m | from file |
| Support structure->Tubular tower | Top diameter | 3.87 m | 5.5 m | from file |
| Support structure->Tubular tower | Top thickness | 0.025 m | 0.020 m | from file |
| Support structure->Tubular tower | Bottom diameter | 6 m | 8.3 m | from file |
| Support structure->Tubular tower | Bottom thickness | 0.035 m | 0.038 m | from file |
Note: two different DTU 10-MW blades are shipped with Ashes, that can be found in the Blade database, corresponding to the blades with and without pre-bending in Bak et al. (2013). Note that the blade without prebending (called DTU 10-MW (no prebend) in Ashes) has a prebending in the in-plane direction. This is due to the definition of the airfoils and the blade in Bak et al. (2013): since the Blade reference line does not go through the Aerodynamical reference point, an in-plane offset is necessary, which results in an in-plane prebending in Ashes.
In addition, we also ship DTU blades with modified polars in the inner part of the blade to deal with the Dynamic stall issue at low wind speeds (see section 4 of the DTU 10-MW document).
In addition, we also ship DTU blades with modified polars in the inner part of the blade to deal with the Dynamic stall issue at low wind speeds (see section 4 of the DTU 10-MW document).
Note: in the specification document for the IEA 15-MW, it is said that the center of mass of the nacelle is downwind with respect to the yaw axis. Since the IEA 15-MW is a direct drive wind turbine, it seems like the center of mass of the nacelle should be upwind. We assume that this is a typo in the specification document and have set the center of mass of the nacelle to be upwind
Note: no information is given in the specifications about the shaft dimensions. Therefore, for the NREL 5-MW and the DTU 10-MW models, we have selected values that produce a correct 1st drivetrain torsion mode (see OC3 Phase I load case 1.2 and ). We have not found information for the 1st drivetrain torsion mode for the IEA 15-MW, therefore the values are somewhat arbitrary.