Wind-turbine Wakes
Developing · Paraphrase rõ nhưng distractor gần nghĩa hơn.
A A wind turbine removes energy from moving air, leaving a wake in which average wind speed is lower and turbulence can be higher. Field measurements show how that wake develops and whether it affects another turbine downstream. B The drawing follows the wind from left to right along one transect. Instrument positions are surveyed carefully because a small change in wind direction can move the wake away from a fixed downstream sensor. C Upwind of the machine, a scanning lidar sends laser pulses through the approaching air. The turbine's rotating surface is represented by the rotor disc, while the turbine nacelle sits at the centre behind the blades and contains the main generating equipment. D Behind the turbine, the wake centreline marks the approximate path of the largest speed deficit under aligned conditions. Farther downstream, a meteorological mast carries instruments that provide a fixed comparison of wind speed and turbulence. E Researchers combine lidar scans, turbine operating records and mast measurements. They separate changes caused by the wake from those produced by atmospheric stability, terrain or a shift in wind direction. F The wake is not a rigid tube and the picture is not to scale. Its width, recovery and movement vary over time, so a single transect cannot describe every operating condition at a wind farm.