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Define initial rotor speed as 4 rpm
Hi, How could I define the initial rotor speed as 4 rpm?
I have tried to set “rpm” in “Rotational Speed Settings” of “Turbine Simulation Page 1”, but no use.
I also tried to load file at “Simulation Input File” in “Turbine Events and Operation” of “Turbine Simulation Page 1”, and following the instructions from “https://docs.qblade.org/src/user/simulation/simulation.html#turbine-events-and-operation”, however the error message like “Could not interpret the file…” jumped out. I also upload the corresponding input file in the attachment (change file name to txt due to upload limitation).
If anyone could help to solve this issue, thank you very much.
BR,
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Hi,
Which turbine are you simulating, and what exactly do you mean by “no use”?
When you set the RPM in the simulation dialog, the turbine should follow that value. If you are running a structural model, select the “Always Fixed” option for RPM. In this configuration the turbine will accelerate to the target RPM during the ramp-up phase and then remain at that constant speed for the rest of the simulation.
When you want to prescribe a varying rpm over time, you should create your own simulation input file using the same column structure as the template you linked. To prescribe RPM as a function of time, you only need the first two columns – time and RPM.
Best,
David
Hi David,
Thank you very much for your reply.
I’m simulating IEA_15MW_MONO_RWT turbine, I’d like to set the initial rotor speed as 4 rpm and free rotation.
I have tried the prescribe file and upload via “Simulation Input File”, however the error “could not interpret the file turbine_ini.txt” jumped out.
The input file of “turbine_ini.txt” was just followed your instruction copied from template from the link above and it was quite simple as followings.
Time RPM
0 4
If you could help to solve the issue, thanks.
BR,
The input file of “turbine_ini.txt” was just followed your instruction copied from template from the link above and it was quite simple as followings.
Time RPM
0 4
Hi David, by the way, I have tried both TAB and space between “Time” & “RPM” and between “0” & “4”, both of them “could not interpret”. FYI.
Hi,
When you select “free rotation” as the RPM setting, the RPM is not prescribed. Instead, it is determined by the balance between the aerodynamic rotor torque and the opposing generator torque. If no controller is defined for the turbine, the “free rotation” setting will cause the rotor to spin freely, with the RPM continuously increasing until either the tip-speed ratio corresponding to Cp=0 is reached or the simulation diverges.
The RPM option you may be looking for is “rampup fixed”. With this setting, the rotor accelerates to the target RPM during the simulation ramp-up phase and then rotates freely. This configuration is typically used for simulations that include a controller.
Regarding the simulation input file: at least two rows of numerical values are required to allow the code to interpolate over time between the entries.
Best regards,
David
Hi David,
It works. Thank you very much for your accurate advise and quick reply.
BR,
