Setting up a met tower

[carriv9]

Good afternoon,
I am fairly new to WAsP Engineering (but I have used WAsP for a couple of years). I am wondering how to accurately set a met tower in WENG, I read the "Quick Start Tutorial" and it seems like you first have to create a site (let's say MT1) and then enter a wind and reference it to the site you created (MT1). However, you can only input one wind direction and one wind speed for that site, how do I accurately input all the wind directions and speeds for a met tower? Do I have to insert multiple winds into that same site (MT1)?
Thank you

[Morten]

The basic wind input to the flow model of WAsP Engineering is a single wind condition. You may insert multiple winds in the project, but usually you have to select only one of these as reference for the calculations. Quite often you also need to specify a height and a site or a group of sites. Some of the ‘tools| scripts’ will iterate over all wind in your project, e.g. ‘Summary site report…’ and ‘Turbulence report…’, or even create a number of winds with different direction and report for these, e.g. ‘Wind speedup and deflection’.


WEng can also operate on extreme wind climates (EWC). This is a little like the mean wind climates in WAsP, i.e. you specify an observed EWC for the reference site and then predict the EWC for other sites.


There are some video demonstrations of basic operations in WEng at https://www.youtube.com/playlist?list=PLrqli3B3J9m4NtU7d373DVWFQMI2iinpb


Cheers,
Morten

[carriv9]

Thanks Morten, so if my wind project has two prevalent wind directions would you recommend me putting both of them as a separate "wind" in the same met mast? Also, what is the reason WEng usually only takes one wind? Why not focus on all the wind directions like WAsP does?
Thank you

[Morten]

It depends a little on the job you need to do. Maybe you want to study a particular problem occurring for a specific wind direction or maybe you need to check turbine safety in general?


For the latter you could try an IEC 61400-1 site assessment, which includes a list of wind conditions to check. You start by creating and selecting a group of turbines sites and their hub height. You also need to create an extreme wind climate by the WAsP Climate Analyst and import this in the WEng project. Then you open ‘Tools| Prepare data for WAT’ from the main menu. This tool will calculate the fifty-year extreme winds for all turbine positions plus tables of wind conditions (shear, turbulence, inclination angle, etc.) for a number of wind directions. You can direct these results to an Excel file and use them as they are or import them in WAT to complete the IEC site assessment.


Cheers, Morten