ysga

WAsP CFD is not free. However, if you are a student at DTU then please ask your supervisor to contact the WAsP group about your needs. Unfortunately, I am not DTU student. It means that, I can not use it as far as I understand.

Hi Seenu, The ruggedness index (RIX) is a measure of the terrain complexity in the area around a site. Delta-RIX (dRIX) is the difference between the RIX numbers at the site of interest and at the reference mast. Terrain complexity leads to uncertainty in linearized flow models, such as the one used in WAsP. But errors related to generalization of the wind climate at reference mast data and errors related to climate prediction at the site of interest will often compensate each other when dRIX is close to zero, i.e. when the RIX numbers for the two sites are comparable. A positive dRIX value means that the terrain around the site of interest is more complex than near the reference mast and the model is likely to over-predicted the wind speed. Best practice is to install a reference mast at the site of interest, let it measure for 2-3 years, and use the local data for the wind resource estimate. You could also try the WAsP CFD model, which generally gives better predictions in complex terrain than the default flow model in WAsP. Best regards, Morten Dear Morten. Is WAsP CFD model free (I have educational license)? Can I use it too?

Dear Brian Ohrbeck Hansen. Possibly I could not express myself. If we think about small wind turbines, some HAWTs do not have yaw or similar mechanisms. So, they can not change their orientation automatically. I already used Climate Analyst for creating .omwc file from my wind speed / direction dataset. After that, I prepared a workspace for my case in WAsP 11 and used the .omwc file which I created via Climate Analyst. I have no problem about .omwc file actually. Obviously this software designed for big wind turbines with yaw mechanism. Possibly, small wind turbines without yaw mechanisms have not been considered. I though that maybe I missed something, missed a setting or something like that but the software has not feature like that. We can not specify a turbine as a HAWT or VAWT. Thanks for the course link but I am not in Denmark and I can not afford to go to Denmark. I can not afford even online course price (800€). Maybe you can consider to discount esspecially for students :) Thanks for the answer. Best regards. ysga

Dear all. As you know that there are 2 type of turbines; vertical and horizontal. The main difference between those turbines is to accept wind from various directions as far as I read a lot of articles (vertical ones accept wind from every direction but horizontal ones accept wind from only one direction which is oriented for (well, in general; esspecially when we think small wind turbines without yaw or similar mechanisms)). As far as I understand, WAsP uses wind direction data too to calculate AEP of wind turbines (we load data to Climate Analyst). But I do not understand that how exaclty use it? If I use VAWT, how can I specify turbine type? Theoritically, it accepts wind from every direction so wind direction would not be a problem. If I use HAWT, how can I specify turbine type and turbine orientation? Let's assume, I oriented the turbine against the wind which is blown south. How can I orient it at the software? Theoritically, it accepts wind from one direction so wind direction would be a problem. We should orient the turbine according the wind direction to get more power. Best regards. ysga.

Dear all. The problem is a misunderstanding about comma usage. As you can see at the attached image at the first message of the topic, AEP is around 24,000. So, comma is been used to specify decimal numbers. 24,000 MWh means 24 MWh not 24 GWh. There is no problem. I thought that it was 24 GWh. Thanks to WAsP support team, esspecially to Duncan. Best regards. ysga.

Dear Duncan. Yes, I want this but I do not understand why it did not become like yours. It shows MWh.

Dear all. An interesting question; AEP calculated MWh at the program but I used small wind turbines and result should be kWh (you can see at the attached image). There is no way to produce 24000 MWh in a year with 10kW wind turbine as you know. Is there a way to change the default unit? Maybe problem occured when I was creating wind turbine as you can see at the attached image. I can not change the red signed area. Best regards. ysga. PRODUCTION UNIT https://ibb.co/j2C81n TURBINE EDITOR https://ibb.co/ktez7S

Hi Ysga, basically if your values of z_0 are all reasonable, and the contours are in the correct places then I would say that's all. This is of course assuming that your map really does match the terrain (e.g. check satellite pictures or site visit), that you have not modified any WAsP parameters from their defaults. But one can not definitely say that your map is "ok" without checking it. with kind regards, Dear Mark Kelly. I just wondered the procedure. So, the procedure is true. I hope that I could simulate the real land well too :) Thanks for your help. Best regards. ysga.

Dear Mark Kelly. I considered the errors which you wrote. There are no errors like that at the map editor. So, I prepared the map which I mentioned at the first message. There are no errors. Is that all? Best regards. ysga.

Dear all. I am trying to complete a project. I am wondering that did I prepare the map correctly? Steps which I followed: I downloaded a map from SRTM database. I entered coordinates, map extension and land roughness. As you know that when you download the map, you have only 2 roughness value; zero and the value which you entered when you preparing the map. I digitized the map for to add new roughness areas according to land's real state (1 for city, zero for sea, 0,5 for suburbs etc.). Is that all? Is my map ready to use in WAsP? Results are changing dramatically according to roughness areas, so I want to it properly. I am using WAsP 11 by the way. Best regards. ysga.

Dear Niels Gylling Mortensen. I really appreciate for the answer. I have some questions too. Dear ysga, Here are a some brief comments to your post: Adding a met. station: we recommend you use the Climate Analyst instead. Remember the geographical coordinates of the anemometer, and export in the *.omwc format for best results. It is done. I used Climate Analyst. Map for WAsP: once you have the SRTM elevation contour and land/sea roughness map, you can add more roughness areas using Google Earth or a scanned paper map. Procedures are described in these course notes: Unfortunately it is not done. I simply could not do that. SRTM map is OK but I could not add more roughness areas using Google Earth. I am trying to do this for now. Obstacle group: model most cities and towns as roughness areas. The obstacle model is only used for situations where the mast is closer than 50 obstacle heights and lower than 3 obstacle heights in relation to the obstacle. So this is a fairly local effect. Well, the anemometer mast and wind turbine will be in the city (the turbine will be small wind turbine on the roof of a building). The exact location of the turbine is not decided yet but there are a lot of obstacles near the turbine and the mast. By the way, they are closer than 50 obstacle heights to turbine and mast obviously. So, should I model all the obstacles? It will be so hard to do that as you can imagine. Instead of that, is it enough to set roughness length to 1 (it is coming from Table of roughness lengths at the WAsP help menu) when I am creating SRTM map file? Wind turbine: you can have information on turbines from the manufacturer or the internet. Also, there are some turbine power and thrust curves in the WAsP library. WAsP cannot calculate these specifications, you must know them from somewhere else. I tried to create wind turbine files without thrust curve and I could do that (with just power curve). However, I do not know the effect this situation on the software. What will happen if I use wind turbine files like this? Is it OK to use like that? My best piece of advice for now is to study the course notes mentioned above carefully; they contain quite a bit of information and links to other sources. Good luck with your thesis! Best regards, Niels WAsP support I am reading the document which you suggest. Thanks for advance. Best regards. ysga

Dear members of the WAsP team. I am writing a thesis about wind turbines and I am using WAsP. Till now, I am following 'step by step example' at the help menu of WAsP. I am just wondering that did I prepare the project properly? It is easy to start a project and add a met. station. After that I am creating .tab file via OWC Wizard (using wind speed data which I have) and add to the project. I can create a map via WAsP Map Editor (using SRTM ver.2 Database). I know the coordinates where I install turbines and I can write land roughness (I am using the value that for big cities, you know the value table in almost every book about wind turbines). I think I did right till this step. What about obstacle group? I am trying to model a city so obstacles are too many. What do you suggest when modelling cities? Should I model obstacles around the turbine for 1km diameter area or maybe just 100m is enough? Do you know any engineering approach about this situation? Also, wind turbines! I am trying to create a turbine for my project via WAsP Turbine Editor (a small wind turbine). But I can not find Ct values from wind turbines' datasheets. Can I calculate somehow via WAsP? I could not find how to do it. If you have any suggestion or warning or just something you want to say, please do not hesitate to say it. I need information desperately. I will be glad if you can help me. Best regards.

Hi Mr. Nielsen. Unfortunately I am not a DTU student; I am not even in Denmark. I will use for learning WAsP's help file apparently. Thanks for the answer. Best regards.

Hello everyone. I have some knowledge about wind energy (I am an engineering student) but I do not know how to use WAsP. I need to learn WAsP for a project and I need some guidance. I examined WAsP website a bit. I found good online English course but the price is 800€. I simply can not afford that as a student (by the way a wish from WAsP education team; you should consider some discount for students :)). I could not find any .pdf guide or something like that. So I want to ask to experienced users; where should I begin? Is there any .pdf guide about using WAsP? Is WAsP's Help Documentation good enough to learn the WAsP from scratch? Do you have any suggestion? Thanks a lot.