JensenAngle {wflo}

For a given distance x, computes the wake cone generated by a turbine.

Description

In Jensen's wake model, a wake cone is generated by a turbine based on the turbine's hub height z, its rotor radius r_0, the terrain's roughness length z_0 and the distance x between the turbine under investigation and a certain second point. z, r_0 and z_0 are taken from the FarmVars settings object, while x is to be provided.

Usage

JensenAngle(x)

Arguments

x

must be a single value. Provide distance in meters.

Details

If a second turbine (B) is in a first turbine (A)'s wake, turbine B's power output must be penalized due to turbulence. This can be performed via Jensen's wake model, but first, it should be checked whether B is actually in A's wake. This function computes the angle of the wake cone generated by turbine A. This can be used together with function JensenTrapezoid PointInPolygon and to see if B is in the wake of A.

Value

JensenAngle returns the (onesided) angle of the wake cone generated by a turbine for distance x.

Author(s)

Carsten Croonenbroeck

References

Jensen, N. O. (1983). A note on wind generator interaction. Roskilde: Risø National Laboratory. Risø-M, No. 2411

See Also

JensenTrapezoid to check whether there are wake effects present. FarmVars for the data object.

Examples

JensenAngle(500)
## For a distance of 500 m, the function returns a wake cone angle of 9.2233 degrees
## (given standard values for z, z_0 and r_0 in the FarmVars settings object).