Hub

In a physical wind turbine, the blades are attached to the hub. In Ashes, the connection to the hub is called hub-to-blade-connection and it's represented by FEM frame elements that go from the blade root to the hub center. The hub-to-blade-connections are identical for all blades, thus their parameters are given for the hub as a whole and not on the individual hub-to-blade-connection.

The model of the hub in Ashes does generally not reflect what a hub looks like in real life, see Wikipedia.

Geometry

Scaling scheme

Scheme for scaling of this part only.


Options:

Parent (default):

The scaling factor is set equal to the scaling factor for the parent part.

Override:

A scale factor (set by you) for thyis part only (i.e. the scale factor set for the parent part is overridden).

Scaling factor

The geometry of this part will be scaled by this factor.


  • Default value: 1
  • Unit:
  • Range: 0.001 — 1000

Radius

The radius of the hub. The root of the blades will be located this distance from the hub center (hub node).

If the rotor has a cone, the distance has the cone angle out of the rotor plane.


If the hub radius is set to zero then the hub has no hub-to-blade connections.

  • Default value: 1.5
  • Unit: $\text{m}$
  • Range: 0 — 100

Mass scheme

Choose how the hub mass is set.

Options:

From radius (default):

The mass is estimated from the hub radius. See Information tab for the calculated value.

User defined:

The mass must be specified in the Mass input field.

Mass

The mass of the hub. The masses of the blades are not included.

  • Default value: 56780
  • Unit: $\text{kg}$
  • Range: 0 — 1e+09

Inertia

The inertia of the hub about the rotor axis (excluding the inertia of the blades).


  • Default value: 0
  • Unit: $\text{kg}\cdot\text{m}^2$
  • Range: 0 — 1e+08

Blade connections

EI

The flexural rigidity (bending stiffness) for all Blade connections

See Wikipedia for information on flexural rigidity.

  • Default value: 10000
  • Unit: $\text{GNm}²$
  • Range: 1e-06 — 1e+12

AE

The axial stiffness for the Hub-to-blade connections


  • Default value: 10000
  • Unit: $\text{GN}$
  • Range: 1e-06 — 1e+06

GJ

The torsional stiffness for the Hub-to-blade connections


  • Default value: 10000
  • Unit: $\text{GNm}²$
  • Range: 1e-06 — 1e+07

m

The distributed mass for the Hub-to-blade connections


  • Default value: 0.001
  • Unit: ${\text{kg}} \over {\text{m}}$
  • Range: 0 — 1e+07