1. Revised extreme wind climate treatment
The extreme wind treatment is still based on the “Annual Maximum” method in combination with the “Probability Weighted Moment” method. A new climate representation is introduced where each year is represented by a large number of extreme-wind samples covering all wind directions evenly. Discretisation in the wind directions data is avoided by including both speed and direction in the samples.
If the wind data are time series of 10-minute averages the updated WAsP Climate Analyst version 2 (published with WAsP Engineering 3) can help you process the data and generate an observed extreme wind climate (OEWC) file to be used by WAsP Engineering 3.
The omnidirectional extreme wind for e.g. 50 years return period (50-year wind, or in general the N-year wind), corresponding to the OEWC, is found by applying Gumbel analysis to the OEWC data set.
2. Improved modelling of regional (generalized) and site-specific extreme winds
The OEWC (new extreme wind climate representation) is by flow-modelling, sample by sample, transformed to the individual sites. From these Predicted Extreme Wind Climate representations (PEWC), the omnidirectional N-year extreme winds are estimated quite analogously to that of the OEWC, but of course applying the Gumbel analysis to the PEWCs.
Similarly, a regional (generalized) extreme wind climate (REWC) may be calculated, but applying to flat, homogeneous terrain standard conditions. A REWC may be used in another WAsP Engineering project within the same climatological region.
The new revised treatment ensures correct back-predictions from PEWC or REWC to OEWC and enables obstacles to be included in the analysis of observed extreme wind climates.
Reporting of extreme wind has been revised along with the improved modelling.
3. Obstacle shelter fully considered
Obstacle shelter effects are now fully implemented – affecting both observed, regional (generalized) and predicted winds. Shelter effects are modelled by WAsP obstacle groups. Non-linear effects on observed winds are computed by iteration.
4. Wind fetch over water revised
The wind fetch over water is now found from a grid-based calculation.
5. All calculated winds saved.
All calculated individual and extreme winds and wind climates are now saved in the project file, thereby avoiding lengthy calculations when reopening the project.
6. Grid maps supported
Elevation and roughness maps in grid (or raster) format may now be used directly to generate projects, in addition to traditional WAsP vector maps.
A vector-to-grid map conversion utility tool is provided, allowing different methods of gridding to be used.
7. Terrain slope maps
A spatial view displaying the terrain slope has now been implemented.
8. Display in Google Earth.
Spatial data may now automatically be displayed in Google Earth - as in WAsP 10.
9. Winds hierarchy reorganised
The winds hierarchy has been reorganised to resemble the WAsP approach more closely. The 'generalised' wind conditions calculated from an observed or geostrophic wind are now explicitly shown and explained.
10. Better support for large flow domains
Flow solutions are now stored in temporary files, which make it possible to operate with larger flow domains when analysing winds from multiple directions, without the risk of exhausting system memory. This is useful when calculating predicted wind climates.
11. Improved WAT integration
WAT - the Wind farm Assessment Tool – is now more smoothly integrated. Scripts are no longer used to calculate the input data for WAT. Note that this requires a licensed installation of WAsP 10. Turbulence results for WAT are optionally exported for multiple reference wind speeds. This is useful for offshore sites since surface roughness over water depends on wind speed.
12. Improved scripts selection
A new scripts selection window makes it easier to understand the available scripts and their selection requirements.
13. Dongle-less licensing system
A new licensing system has been introduced, no longer requiring a hardware dongle. You simply register the software using a license file which is e-mailed to you after purchase of the software. See the new WAsP software licencing guide here. |