PhD Positions Cluster Wake Control

Wind turbines packed in large offshore wind farms hinder each other by the formation of turbulent wind wakes, which lead to large efficiency losses at downstream turbines. With the growing number and attention for wind farms, it becomes clear that the wake effect is not only present on a turbine-to-turbine level, but also on a farm-to-farm level. On a wind farm level the energy extraction by each individual turbine cumulates, leaving a pronounced wake in the downstream region, the so-called cluster wakes.

Wind turbine wakes have been studied extensively and the state-of-the-art includes various strategies for mitigating their effects on downstream turbines, amongst others accelerating the wake recovery by dynamically exciting the blade pitch angles, known as Active Wake Mixing (AWM). In contrast, the collective wake of an entire wind turbine cluster is not yet fundamentally well understood, and no strategies have yet been presented to mitigate this. However, the effect of cluster wakes on the power generation of neighboring wind farms is expected to be of major importance considering the extent of planned offshore wind farms and their proximity to each other. In the CLUSTERWAKE project, we will study the novel concept of Active Cluster Wake Mixing (ACWM), which is capable of decreasing the length of the wake downstream of the wind farm. Active Cluster Wake Mixing generates dynamic force patterns over the wind farm, by adapting the thrust of the individual turbines. These patterns are designed to trigger instabilities of the wind farm cluster wake.

Within the CLUSTERWAKE project we will have two open positions: one with a focus on the aerodynamics and high fidelity simulations of active cluster wakes and the second with a focus on the control system (the optimal pattern to trigger the instabilities).

REQUIREMENTS