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Twist

Hi David,

Id like to run a simulation where only one blade will be twisted and see what impact it can have on the turbine. In creating turbine definition only one blade desing can be choosen. Is there another way to do it? I checked the input files, but they define only structural properties.

 

BR,

WT

Hi WT,

In general, QBlade is not designed to simulate a single rotor that incorporates a nonuniform aerodynamic blade designs. However, there are methods you can use to approximate this scenario:

  1. Blade Damage Feature: This option is available in the “Advanced Blade Design” tab within the blade design module. When you’re creating a blade, you can use this feature to modify the polar definitions for a specific blade number in a rotor design. It essentially allows you to apply different aerodynamic characteristics to an individual blade.
  2. ERRORPITCH_X Keyword for Structural Simulations: If your simulation includes a structural model, you can utilize the ERRORPITCH_X keyword. This function enables you to introduce a pitch error to blade X in the rotor. By adjusting this setting, you can alter the pitch of a selected blade by a specified amount. This creates an aerodynamic imbalance, similar to the effect of having blades with different designs.

These methods provide a way to simulate a rotor with nonuniform blade designs, despite the limitations of QBlade to directly model such a configuration.

BR,

David

Hi David,

I used error pitch and error yaw in structural data file to see how produced power, generator electric power and aerodynamic power changes. Well, when i added 1,3 and 5 degree on one blade, all of them were below basic turbine.   But when I went the other way the same steps, the production and the rest of the graphs were above base. How is that possible when they should be below it, too? And when it comes to yaw it is as I assumed that is, production and both capacities are below the baseMaybe Im doing something wrong  or something I dont understand.

 

BR,

WT

Hi WT,

the “response” that you are getting from the turbine after changing these parameters very much depends on the operational point that the turbine is operating at (i.e. the tip speed ratio). Therefore, it very much possible that changing the blade pitch can result in some performance gain (at the cost of much larger cyclic loads). If you are operating at the design tip speed ratio however, introducing pitch errors is more likely to decrease performance rather than improve it. But it all depends on the rotor design and operating conditions.

BR,

David