Effects of inflow turbulence intensity and turbine arrangements on the power generation efficiency of large wind farms
Journal
Wind Energy
Journal Volume
23
Journal Issue
7
Pages
1640-1655
Date Issued
2020
Author(s)
Abstract
In this study, we conduct a series of large-eddy simulations (LESs) to study the impact of different incoming turbulent boundary layer flows over large wind farms, with a particular focus on the overall efficiency of electricity production and the evolution of the turbine wake structure. Five representative turbine placements in the large wind farm are considered, including an aligned layout and four staggered layouts with lateral or vertical offset arrangements. Four incoming flow conditions are used and arranged from the LESs of the ABL flow over homogeneous flat surfaces with four different aerodynamic roughness lengths (i.e., z0 = 0.5, 0.1, 0.01, and 0.0001 m), where the hub-height turbulence intensity levels are about 11.1%, 8.9%, 6.8%, and 4.9%, respectively. The simulation results indicate that an enhancement in the inflow turbulence level can effectively increase the power generation efficiency in the large wind farms, with about 23.3% increment on the overall farm power production and up to about 32.0% increment on the downstream turbine power production. Under the same inflow condition, the change of the turbine-array layouts can increase power outputs within the first 10 turbine rows, which has a maximum increment of about 26.5% under the inflow condition with low turbulence. By comparison, the increase of the inflow turbulence intensity facilitates faster wake recovery that raises the power generation efficiency of large wind farms than the adjustment of the turbine placing layouts. © 2020 John Wiley & Sons, Ltd.
Subjects
large eddy simulation; power output; surface roughness; turbulence intensity; wind farm layout
SDGs
Other Subjects
Atmospheric thermodynamics; Boundary layer flow; Boundary layers; Efficiency; Electric power generation; Electric utilities; Large eddy simulation; Surface roughness; Turbines; Turbulence; Wakes; Wind power; Aerodynamic roughness length; Electricity production; Power generation efficiency; Power out put; Turbulence intensity; Turbulence intensity level; Turbulent boundary layer flow; Wind farm layouts; Electric power system interconnection; aerodynamics; boundary layer; energy efficiency; inflow; large eddy simulation; power generation; turbulence; wake; wind farm; wind turbine
Type
journal article