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Well, maybe not the world, maybe just of CZcams, but thanks a lot!

Thanks!

Noted, thanks for the suggestion! You can also try yourself if you feel like, you can try Ashes at www.simis.io

It's called Ashes, you have more info in the description

What version of Ashes are you using?

free version 3.20

@@sportslover5679 Right, it is a feature that is only available in Ashes 3.21 (free doesn't matter, the free version has all the features but can only be used for evaluation for two weeks). You can send us an email at support@simis.io and we can send you a link to download 3.21

It depends on your use case. Get in touch with us at sales@simis.io and we can have a chat about licencing options for you

We use Stig Oye's model, you can read more on it here: www.simis.io/docs/bem-algorithm-unsteady-bem#2 In what context are you asking? Do you use aerodynamic software yourself?

Hi, thanks for the question Yes, it is easy to delete the batches, can you send us an email at support[at]simis.io?

Thanks!

You can export all graphs with the "Generate report" button. Please ask the question on our forum (here www.simis.io/q-and-a/) so I can add links and screenshots

@@AshesWindTurbineSimulation Thank you so much. Can we download the data and create graphs in Excel or other software?

@@sportslover5679 yes, you can have a look at our user manual here to see how to do that: www.simis.io/docs/sensors-export-the-data

Hi, what do you mean with 'matter'? Are you wondering about whether it will still trigger the eigenfrequency, its impacts on the loads...

@@AshesWindTurbineSimulation correct, that's what I meant :)

@@33Mysterious Still not sure which one of the two you mean :) About triggereing the eigenfrequency, yes it still will. The support structure eigenfrequencies are virtually the same in all directions About impact on the loads: for fatigue loads, what matters is how much aerodynamic damping there will be, so it has to do with whether the direction of the waves match the orientation of the blades

Are you part of the NTNU course? If so, you should ask your teachers (we don't have it)

Very happy to read this thanks a lot!

Great question! Obviously it depends on the wind and wave conditions, but for example in the case of a storm, in our experience, the wave loads are dominant for ultimate limit state. That is very easy to check though, just run two simulations, with the rotor parked and in operation

As far as we understand, with this controller, the blades are pitched to keep the rotational speed of the rotor constant at the rated RPM: when the wind speed increases, the aerodynamic torque also increases and that makes the RPM increase, so the blades are pitched to decrease the RPM back to the rated value. But the controller doesn’t know (and doesn’t care!) why the RPM increased: is it because the turbine is moving forward or because the incoming wind has increased? It doesn’t matter, the controller will just pitch the blades. The point of the video is that if the speed at which you increase the blade pitch is not adequate, you might introduce negative damping, so it is something to be careful about. But wind turbine controllers are extremely complex, and I am sure there is a lot of thought put into how controllers interact with floater stability. We are not control experts, it would be great if someone that is could comment on this topic.

If you are studying the wake effect, you don't need to create multiple wind turbines. What you need is another software (such as DIWA) that will create a wind field that incorporates the effect of an upstream wind farm, and then use that wind field on the wind turbine in Ashes. in this video, we created multiple wind turbines only for illustrative purposes, but the interaction between them is not computed by Ashes

That's really cool to hear, glad it was helpful! What high school was that? Do you think more students there could benefit from Ashes? Feel free to write to us at support@simis.io to have a chat about this!

What data does your file contain? Is it a wind field (for turbulent wind) or a time history of one single wind speed at the hub? In both cases the answer is yes, but it will be done in different ways

The wind data was collected from a pre installed macht, that has collected information for a span of a year.@@AshesWindTurbineSimulation

Yes there is an option, can you post your question on our forum (www.simis.io/q-and-a) so that we can reply with pictures?

@@AshesWindTurbineSimulation Where is it? and how ?

@@sportslover5679the forum is here: www.simis.io/q-and-a and the option to export graphs is an inon on the top right corner of the graphs pane. If you post a question on the forum I can add a picture showing where it is

Thanks, we replied to the email you sent us as well. In general, when you have a question like this, it is better that you write to us at support@simis.io, so that you can include a more detailed description of the issue together with screenshots of the issue

A big difference between airplane wings and wind turbine blades is that wind turbine blades are rotating, which means that they experience both the incoming air flow (due to the wind) and what we call a rotational wind velocity due to their motion through the air. The sum of the two is the relative wind. As you can imagine, the further along the blade, the higher the speed of the blade through the air and thus the higher the relative wind. That is why the blades cannot be ‘flat’ as for airplanes but need what we call a twist angle that varies along the blade, to face the relative wind best. And if the blades were feathered, they would not be aligned with the relative wind. This video is relevant: czcams.com/video/OOP6Mbn0Gbw/video.html

@@AshesWindTurbineSimulation So why can't the turbine mechanism be designed to swivel andface the oncoming wind???

@@johnblack4318 Right, do you mean turning the whole rotor so that it faces the wind (rather than individual blades)? Yes, that is done, it's called yawing the turbine. Feel free to download Ashes (www.simis.io) and give all that a try

All (arguably) utility size wind turbines can be feathered and they are feathered when the control system decides to shut down due to too high winds (showing how a wind turbine shuts doen should probably have been a part of this vid). Usually, though, a wind turbine that is shut down is idling, i.e. it is (still) rotating, but very slowly. This can be quite easily simulated in Ashes using the IEA 15MW reference turbine (that ships with Ashes) and its ROSCO controller (that also ships with Ashes). However, you do have to manually change the input file for ROSCO to shut-down mode. If you do that, the wind turbine will start shutting down when the pitch is at approximately 22 degrees and increase the pitch to approximately 90 degrees. We will probably make a vid soon show exactly this - so, like, subscribe and press the bell ;-)

We have a benchmarking framework where we run tests and compare results with other software, full-scale data, experimental data and results from previous versions of Ashes. We add new tests on a daily or weekly basis, every time we want to test something new (for example when there is a new feature). By running the tests every night we make sure that the results are always up to date. The tests are run every night and published every new release (see www.simis.io/docs/validation-benchmarks-latest-reports for the latest reports). We think it is crucial that the tests are public and fully reproducible, so all the data needed to run the tests yourself are available as well. This video explains how to understand and reproduce the tests: czcams.com/video/GkoBcUybSos/video.html And this blog post gives more details about how the whole thing works: www.simis.io/pages/blog/

Absolutely, any model can be fully customised (including the blades). But you will have to have a good definition of what 'working the best' means, as there are many parameters to consider! Feel free to download and try Ashes for free at www.simis.io

Hey i really like the app, but is it possible if we could connect with discord for faster chatting, i'm doing this for my school project. or is here okay?@@AshesWindTurbineSimulation

No, semi-colon does not work, but we could add it

The script is not shipped with the current version of Ashes, but get in touch with us (support@simis.io) and I will happily share it with you. And the graph is generated by Ashes, not by the script. There are a couple of ways to plot graphs, the simplest is probably to right-click on the load you want to plot and add a sensor

Very happy you liked it!

Unfortunately that is a quite old model that we created with an older version of Ashes, and we don't have it anymore. I cannot remember the specific settings that we used, but I'll see if I can recreate it

Sincerely thanks for your kindness.@@AshesWindTurbineSimulation

What quantity would the sensor show?

For example, use the aerodynamic force times the displacement to get the aerodynamic work of each blade element; Take the sum as total aerodynamic word of blade. The aerodynamic damping coefficient is obtained again without dimensionalization.@@AshesWindTurbineSimulation

Similar to the definition of aerodynamic damping of aircraft wings. When the aerodynamic force does positive work, it is negative aerodynamic damping, and the structure is in self-excited loose vibration.@@AshesWindTurbineSimulation

@@wuhongxin_wind very interesting, thanks for the suggestion!

3.21 will be released early next year, january or february. Is there a specific feature from 3.21 that you need?

Thank you for your reply. When I followed the video operation, I found that 3.20 could not run as the video. like the"Make rotor characteristics curves" at 05 video and the matlab tools.@@AshesWindTurbineSimulation

@@wuhongxin_wind That is correct,that is a feature of Ashes 3.21. Please send me an email at loup.suja@simis.io and I will try to help you

You could also have gusts of wind in onshore wind turbines, that would trigger some vibrations, and in that case aerodynamic damping would be beneficial to the structural integrity of the wind turbine as well. But aerodynamic damping is inherently taken into consideration in the time simuation (at least with Ashes), you can't turn it off...

XFoil comes with the software, so you could generate different polars for your airfoils for different surface roughnesses and then compare how they perform

When you say 50 ms, I assume you are talking about wind velocities, right? And what do you mean with 'taking into account acceleration vs time'? Do you want to plot a certain acceleration as a time series? Which acceleration is that?

@@AshesWindTurbineSimulation Yes, it is the wind speed, and when I say acceleration vs. time it is the data I need to perform a dynamic analysis on a structure.

@@manu3308 ok, then you can definitely do that in Ashes, I suggest you download it and try it for free from www.simis.io. The best place to see how to do use Ashes is through our tutorials on our CZcams Channel, or our user manual (www.simis.io/docs). If you have any question don't hesitate to post it in the forum (www.simis.io/q-and-a ).

@@AshesWindTurbineSimulation Thank you very much for replying, you know that when I activate the forum it shows 404 - Page not found. I take advantage of your kindness if you have a specific tutorial to which I can direct me and how to download the value in a txt or excel file to model that spectrum in Etabs. I am modelling an elliptical shaped roof and the idea is to model the dynamic wind analysis using a spectrum or time history with wind loads.

​@@manu3308 Sorry I had mistyped the link: it is www.simis.io/q-and-a Our tutorials are here, the list is in order so you can start with the first video: czcams.com/play/PLkxg02c9QfHcXmDkFN8FI4-XATQuL7S2I.html And we don't have a video tutorial on how to download the data, but you can find that info on our user manual here: www.simis.io/docs/sensors-export-the-data

You are 100% right Roger, actually that discretisation is also sometimes called "Equal area discretisation". And about higher frequencies being poorly represented, in Ashes you do have the possibility to subdivide the higher frequency components into smaller bins, to get a finer discretisation at the tail of the spectrum. This is from our Theory manual (here, in case you are interested: www.simis.io/docs/water-particle-kinematics-irregular-waves#3): "...the last components cover a wide frequency range compared to the other components. This means that there will be comparatively fewer components modeling the higher frequencies of the spectrum, which can be a problem when simulating the response of certain structures. [...] In order to solve this issue, it is possible to further divide each of these frequency bins into smaller bins. The parameter Frequency delta limit allows you to set a maximum frequency width for each component as a product of the average difference between two consecutive frequencies. [...] this implies that you can end up with more than N components [that's the input from the user], and that the extra components will not have the same energy as the rest."

You can export all graphs with the "Generate report" button. Please ask the question on our forum (here www.simis.io/q-and-a/) so I can add links and screenshots

You mean whether the blades are pitching? Yes they are, you can see the value in the Control pane at the bottom of the screen

It's called Ashes, you can find a link in the description to download it

Because the pressure distribution around the airfoil changes to a configuration that gives a smaller lift force. You can actually try that with Ashes, if you use the Investigate option in the airfoil database (see www.simis.io/docs/databases-airfoil-database)