TY - JOUR
T1 - Effects of atmospheric stability on the performance of a wind turbine located behind a three-dimensional hill
AU - Liu, Luoqin
AU - Stevens, Richard J.A.M.
N1 - Elsevier deal
PY - 2021/9
Y1 - 2021/9
N2 - Understanding the effect of thermal stratification on wind turbine wakes in complex terrain is essential to optimize wind farm design. The effect of a three-dimensional hill on the performance of a downwind turbine is studied by performing large eddy simulations for different atmospheric conditions. The distance between the hill and the turbine is six times the turbine diameter, and the hill height is equal to the hub height. It is shown that the hill wake reduces the power production of the downstream turbine by 35% for the convective boundary layer case under consideration. However, surprisingly, the wind turbine power production is increased by about 24% for the stable boundary layer case considered here. This phenomenon results from the entrainment of kinetic energy from the low-level jet due to the increased mixing induced by the hill wake. This effect strongly depends on the Coriolis force-induced wind veer. The increased turbulence intensity by the hill results in a strong increase in the forces experienced by the blades, which suggest the turbine is experiencing much higher unsteady turbulence loading. It is shown that the increase in the power fluctuations may not fully reflect the increase in the force fluctuations on the blades.
AB - Understanding the effect of thermal stratification on wind turbine wakes in complex terrain is essential to optimize wind farm design. The effect of a three-dimensional hill on the performance of a downwind turbine is studied by performing large eddy simulations for different atmospheric conditions. The distance between the hill and the turbine is six times the turbine diameter, and the hill height is equal to the hub height. It is shown that the hill wake reduces the power production of the downstream turbine by 35% for the convective boundary layer case under consideration. However, surprisingly, the wind turbine power production is increased by about 24% for the stable boundary layer case considered here. This phenomenon results from the entrainment of kinetic energy from the low-level jet due to the increased mixing induced by the hill wake. This effect strongly depends on the Coriolis force-induced wind veer. The increased turbulence intensity by the hill results in a strong increase in the forces experienced by the blades, which suggest the turbine is experiencing much higher unsteady turbulence loading. It is shown that the increase in the power fluctuations may not fully reflect the increase in the force fluctuations on the blades.
KW - UT-Hybrid-D
KW - Atmospheric stability
KW - Large eddy simulation
KW - Power output
KW - Three-dimensional hill
KW - Wind turbine wake
KW - Atmospheric boundary layer
UR - http://www.scopus.com/inward/record.url?scp=85106391917&partnerID=8YFLogxK
U2 - 10.1016/j.renene.2021.05.035
DO - 10.1016/j.renene.2021.05.035
M3 - Article
AN - SCOPUS:85106391917
VL - 175
SP - 926
EP - 935
JO - Renewable energy
JF - Renewable energy
SN - 0960-1481
ER -