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-   -   Wind turbine rotation through UDF in FLUENT (http://www.cfd-online.com/Forums/fluent-udf/123681-wind-turbine-rotation-through-udf-fluent.html)

Shamoon Jamshed September 18, 2013 13:50

Wind turbine rotation through UDF in FLUENT
 
Hi,

I am modelling a wind turbine blade. I want in FLUENT that I specify inlet velocity at its inlet and the FLUENT let itself rotate the blade due to this wind velocity. However, I will specify the parameters (not rpm obviously) through UDF as I want to use dynamic mesh for this purpose. Please tell me if this approach is OK.

Secondly, I am stuck in UDF because all the UDFs I have had serached up until now have used rpm inside the UDF. This is not required (perhaps) in my case because I want to calculate FLUENT its rpm throuh rotating the turbine. In this case what parameters should I specify, please help me out.

Regards,

jdrch September 18, 2013 20:04

You might be better off using an MRF for this. See the FLUENT documentation for details.

Shamoon Jamshed September 19, 2013 00:57

The MRF still requires the user to input RPM while we want Fluent itself to determine rpm or give torque while we input only UDF and inlet velocity

jdrch September 19, 2013 05:54

Quote:

Originally Posted by Shamoon Jamshed (Post 452467)
The MRF still requires the user to input RPM while we want Fluent itself to determine rpm or give torque while we input only UDF and inlet velocity

I see. Yeah I've never back-calculated RPM before.

Kokemoor September 19, 2013 10:59

Inlet velocity and turbine rotation rate are inputs, torque is an output. To find torque, you need to know the rotation rate. If you want to determine rotation rate given a certain torque (perhaps no torque or just friction at the axle) I don't believe there's a straightforward way. I see two reasonable options:

You could write a UDF controlling an MRF that calculates the torque every N iterations and guesses a new rotation rate that will (hopefully) result in your target torque.

You could write a UDF for a transient dynamic mesh that accelerates the turbine every time step based on the torque as d\omega=\frac{Tdt}{I}. The Six DOF dynamic mesh solver may be appropriate, but I've never used it, and can't say for sure.

Bharatt November 29, 2013 08:25

FLUENT--let itself rotate the blade due to this wind velocity
 
Quote:

Originally Posted by Shamoon Jamshed (Post 452427)
Hi,

I am modelling a wind turbine blade. I want in FLUENT that I specify inlet velocity at its inlet and the FLUENT let itself rotate the blade due to this wind velocity. However, I will specify the parameters (not rpm obviously) through UDF as I want to use dynamic mesh for this purpose. Please tell me if this approach is OK.

Secondly, I am stuck in UDF because all the UDFs I have had serached up until now have used rpm inside the UDF. This is not required (perhaps) in my case because I want to calculate FLUENT its rpm throuh rotating the turbine. In this case what parameters should I specify, please help me out.

Regards,

Hello Jamshed,

I am also trying to simulate exact the same(FLUENT--let itself rotate the blade due to this wind velocity). but don't have any idea/clue how to proceed. i performed some simulations by using dynamic mesh(rotary motion to mesh) and was able to get results. but for this case, my search is on :confused: .could you please help me with this? did you finish with your case?

P.S-could you share any of the UDF's you found for this simulation! please

Thanks in advance

Regards,
Bharatt

ntsphong2 January 9, 2014 23:02

same my problem, I don't have any idea :(:(
P.S-could you share any of the UDF's you found for this simulation! please ;)
thanks so much
email: nguyenkhangninh.hk@gmail.com

belariad January 18, 2014 12:06

wind turbine spanwise distribution of lift and drag
 
hi;
i am modelling a flow over a wind turbine blade using fluent, i want to know how can i plot the span wise distribution of the lift force, i mean that i created 10 iso-surfaces on the blade (span wise direction) and now i want to know the value of lift and drag on each one.
i think that i need a UDF or Scheme programming to do this.
can you help me.


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