| Short Time Interval Window | |
This feature is coming soon to Windographer 5.
This window displays vertical wind speed profile and hodograph (mean speed and direction) averaged over time intervals as short as a single time step, and lets you step through the time series to see how the speeds and directions change in time. To access this window, choose from the menu.
Tip: You can use the Short Time Interval window only if you have the Professional or higher edition of Windographer. Please visit www.windographer.com for information on the pricing and capability of each edition.
The vertical wind shear profile graph shows the mean wind speed for each wind speed sensor for the current time interval, along with the logarithmic law and power law profiles that best fit those mean wind speeds. The corresponding table lists all of the wind speed sensors, their heights above ground, the number time steps with valid data points in the current time interval, and the mean wind speed.
The mean speed and direction wind rose shows the mean wind speed as a radial arrow on a wind rose, located at the mean wind direction. The mean wind direction is a vector calculation. If you have direction data at several heights, you can visualize speed and direction shear with this graph. The corresponding table lists all of the wind direction sensors (identified by height), the associated mean wind speed, the vector mean wind direction, and the associated number time steps with valid data points in the current time interval for each. Note that vector mean wind direction can only be calculated in time steps that also contain valid wind speed.
Use the Format buttons to see the results in graphical or tabular form. The tabular results report additional information including the number of time steps included in the calculation.
Tip: You can specify which wind speed column should associated with each wind direction column on the Configure Dataset Window. This is a property of each wind direction data type. If you choose <None> then this wind direction sensor will not be shown in graph or table.
In the Averaging interval box, enter the number of time steps over which you wish to analyze the wind shear. The screenshot below shows the shear averaged over 144 ten-minute time steps (24 hours).
The time series graph highlights the current time interval. Using the scroll bar and zoom buttons below the graph to see any portion of the dataset.
Adjust the Jump Size and use the large arrows to step through the time series data and quickly see the changes in the wind shear profile. Right click on the graph and use the Properties window to set a fixed minimum and maximum for the x-axis or radial axis to facilitate comparison in different periods.
Click anywhere in the time series graph to select a new start time for the averaging interval.
In the example above, the pink 'Tower shading' flag applies to a segment of the 'Speed 60m A' data, resulting in only 126 valid points for that data column over this time interval. Although there appear to be 144 valid Direction 60m data points, only 126 are used in the vector mean direction calculation because wind speed is also required for this calculation. Default flag filtering determines the number of valid points for the calculations, meaning that Windographer will exclude from this calculation any data point flagged with a flag to be excluded from calculations by default.
Right-click any graph to change its properties, copy the image to the clipboard, or export it to a file. Right click any table to export it to a text file or to copy it to the clipboard.
See also