Gil

to make more clear for question 1, which values do WAsP take from 3km to 30km if values from roughness lengths cannot be considered? , e.g. zero roughness value or last roughness value observed at 3km or something else?

Dear Morten, Thanks for your confirmation. it means that the WAsP wake model applies for the entire wind farm with the same values and no chances to separate the wake parameters for turbine groups. Thanks for screen dump and detailed explanations. as you pointed out, that was the my concerns "the terrain is complex and elevation difference is higher even though RIX numbers are not high". Regars, Gyeongil

Dear Morten, Thanks for your confirmation and answers. if "10 different roughness changes were observed by WAsP in short distances (let's say in 3km), WAsP did not consider roughness changes any further in distances" is true, then (Question 1) what is the impact on AEP if further distance roughness changes are not considered (e.g. from 3km up to 30km)? when I was in WAsP course in DTU, i have learned that most critical information of roughness chances is border (100 ~ 150 x Hub heights) as this affects in transition boundary layer. in this case it seems WAsP did not correctly consider. (Question 2) to my understanding roughness rose is not anymore valid since WAsP 11.x and later version. Does WAsP 12.x use now again roughness rose? Could you clarify two additional questions? Regards, Gyeongil

Dear Team, based on old knowledge and after discussion with a colleague, i am a bit confused about how WAsP handles many roughness changes in short distances. from a colleague, she mentioned if 10 different roughness changes were observed by WAsP in short distances (let's say in 3km), WAsP did not consider roughness changes any further in distances (in this case from 3km up to 20km - typical map size and boundary). is this true? Based on recent improvement and implementation of QGIS instead of Map editor, the user can digitize more detailed roughness. if the above is applied, then i am wondering the impact. could you explain me and advise me how WAsP handles many roughness changes in short distances? regards, Gyeongil

Dear Team, I have two masts at the site and more than 20 wind turbines are planned. during test simulation i found out wake calculations by two different masts are quite different and in the end energy level differences are also high. i have not used default settings of wake settings in PARK2 but try to adjust and simulate. one parts of turbine groups are close to mast 1 and another groups are close to mast 2. the elevation difference between mast 1 and 2 are almost 200m asl. that is why I considered it makes more sense to separate two groups. however, all wind turbines should be considered as a whole. Are there any way to calculate wakes by applying different wake parameters in a wind farm? i am thinking to make the results separately and merge together. but in this case, i should consider again the wake by each group. it would be great if you could advise me how to apply in WAsP. regards, Gyeongil

Dear Team, i am doing resource assessments in forest site with multi-masts mainly based on WAsP. Western and southern parts of the site have a steep slope > 16.7 degree, so that I ordered WAsP-CFD. i read most of forest issues in this forum and also from webpage: https://www.wasp.dk/software/wasp-cfd/flow-model to understand better of WAsP-CFD. However I still did not fully understand. I have some questions below. (Question 1) Are there any benefit of WAsP-CFD focusing on forest area? based on webpage above, it seems to me that WAsP-CFD use/interpret roughness data differently. (Question 2) if WAsP-CFD has zero benefit compared to WAsP in terms of forest, should I apply same displacement heights in WAsP-CFD that were applied to WAsP? (Question 3) based on WAsP, three main inputs are oro + rou + obs. How are obstacles dealt with in WAsP-CFD if they are not a part of input before run? My last WAsP course was long time ago and i have used 3rd party CFD tools to handle forest. i think that could be the reason why I am still confused to understand how WAsP-CFD works. Could you please advise/guide me with details? Thanks Gyeongil

Hi Rogier, Current menu shows the following: WASA Wind Atlas downloads --> WASA Observational Wind Atlas UPDATED (Dec 2018) : The WASA observational wind atlas contains observed (OWC) and generalized (GWC) wind atlas data sets for the 15 meteorological stations established and operated by the WASA project. Observed wind climate files from the 15 WASA stations. The data mostly cover an eight year period from November 2010 to September 2018 for the WASA 1 masts and a three-year period from November 2015 to October 2018 for the WASA 2 masts. The WAsP workspace WASA 1+2 validation 2018.wwh contains data and sample maps for the 15 meteorological stations in the Wind Atlas for South Africa. then they are linked to: Observed wind climate (OWC) Generalised wind climates (GWC) WAsP analysis of WASA stations (WWH) if you have those files, it would be great but if not, I think I need to download all data and process by myself. Thanks. Gyeongil

Dear team, i am trying to use WAsP for south African projects and found out many data is already available from webpage: https://wasadata.csir.co.za/. in the section "WASA Observational Wind Atlas" there are links to DTU servers but it seems not working anymore. // The following files are not yet available on the local server, but can be downloaded from the DTU server Observed wind climate (OWC) Generalised wind climates (GWC) WAsP analysis of WASA stations (WWH) // Are those data still available from DTU server? if yes, could you please provide me the new/updated links? if not, are there any way to download those data sets? please advise me. BR, Gyeongil