Large Eddy Simulation of clearings in forest and their effect on wind turbines
Licentiate thesis, 2018

When the number of wind farms increases, the number of wind turbines placed in forested areas will also increase, this is because of the large forest areas in Sweden. When the wind turbines are placed in forested areas the fatigue loads increase drastically, so their maintenance costs increase making them less profitable. In this work clearings in forest are studied to be able to increase the electrical power generated by the wind turbines and decrease the fatigue loads to make them more profitable.
The approach in this work is to use Computational Fluid Dynamics (CFD) with the Large Eddy Simulation (LES) turbulence model coupled to an aero elastic solver that solves the dynamic response of the wind turbine.
Here Ryningsnäs in Sweden is investigated with a homogeneous forest, the current clearing and an extended clearing. The electrical generator power was highest for the current clearing. But the fatigue loads were both higher and lower than the homogeneous forest depending on which part of the wind turbine that was investigated. The extended clearing nearly always had the lowest fatigue loads but unfortunately also the lowest electrical generator power. Further optimization of the clearings and the wind turbine locations in relation to them is needed to find the sweet spot where the fatigue loads are lower and the electrical generator power is higher.

OpenFOAM

FAST

Wind turbine

SOWFA

forest clearing

CFD

ALM

LES

EA, Hörsalsvägen 11
Opponent: Stefan Ivanell, Uppsala universitet, Sverige

Author

Johanna Matsfelt

Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics

Driving Forces

Sustainable development

Areas of Advance

Energy

Infrastructure

C3SE (Chalmers Centre for Computational Science and Engineering)

Subject Categories

Fluid Mechanics and Acoustics

Publisher

Chalmers

EA, Hörsalsvägen 11

Opponent: Stefan Ivanell, Uppsala universitet, Sverige

More information

Latest update

5/25/2018