Table of Contents

IAGModel

https://bladednextgen.dnv.com/schema/0.4.1/Settings/AerodynamicSettings/DynamicStall/IAGModel.json

The IAG dynamic stall model.

  • DynamicStallType: string = IAGModel
  • UseDynamicPitchingMomentCoefficient: boolean
  • StartingRadius: number
  • EndingRadius: number
  • SeparationTimeConstant: number
  • UseLinearFitGradientMethod: boolean
  • UseImpulsiveContributions: boolean
  • PressureLagTimeConstant: number
  • VortexLiftTimeConstant: number
  • VortexTravelTimeConstant: number
  • AttachedFlowConstantA1: number
  • AttachedFlowConstantA2: number
  • AttachedFlowConstantB1: number
  • AttachedFlowConstantB2: number

A type of DynamicStall

Properties

UseDynamicPitchingMomentCoefficient: boolean, optional

If true, the dynamic pitching moment coefficient will be used. This option is enabled by default. It is not recommended to disable this option for blades with a torsional degree of freedom because the so-called 'pitch- rate damping' term of the moment coefficient is typically important to keep the blade torsional mode stable.

default = True

StartingRadius: number, optional

The fraction of the radius outboard of which the dynamic stall model will be used. A value of 0.0 means that dynamic stall is applied from the blade root.

default = 0.0

EndingRadius: number, optional

The fraction of the radius outboard of which the dynamic stall model will be switched off. A value of 1.0 means that dynamic stall is applied until the blade tip.

default = 0.95

SeparationTimeConstant: number, optional

A dimensionless time constant, given in terms of the time taken to travel half a chord. It defines the lag in the movement of the separation point due to unsteady pressure and boundary layer response.

default = 3.0

UseLinearFitGradientMethod: boolean, optional

If true, the linear fit polar gradient is used to reconstruct the inviscid polar data. The fit is performed only within the linear polar regime that is searched automatically between the zero lift AoA to AoA = 7 deg. This approach is more suitable for polar data sets where the lift coefficient slope is not straight around 0 deg angle of attack. It is recommended to activate this option for more accurate computations. This option is turned on by default.

default = True

DynamicStallType: string

Defines the specific type of DynamicStall model in use. For a IAGModel object, this must always be set to a value of IAGModel.

UseImpulsiveContributions: boolean, optional

Enabling the impulsive contributions in lift and moment coefficient.

default = True

PressureLagTimeConstant: number, optional

The lag between the pressure and the lift.

default = 1.7

VortexLiftTimeConstant: number, optional

The rate of decay of the vortex induced lift that is generated when airfoils undergo a rapid change in angle of attack towards positive or negative stall.

default = 6.0

VortexTravelTimeConstant: number, optional

The time constant that controls the duration of the vortex induced lift that is generated when airfoils undergo a rapid change in angle of attack towards positive or negative stall.

default = 6.0

AttachedFlowConstantA1: number, optional

The constant A1 for the IAG dynamic stall model to control the attached flow states.

default = 0.3

AttachedFlowConstantA2: number, optional

The constant A2 for the IAG dynamic stall model to control the attached flow states.

default = 0.7

AttachedFlowConstantB1: number, optional

The constant B1 for the IAG dynamic stall model to control the attached flow states.

default = 0.7

AttachedFlowConstantB2: number, optional

The constant B2 for the IAG dynamic stall model to control the attached flow states.

default = 0.53