is it necessary to multiply by number of blades with moment to calculate the power?

er_ijaz · November 16, 2013, 05:48

Hi
I have done the simulation of wind turbine using MRF analyis. I have not done any symmetric analysis. I have done whole blade simluation. But when I calculated power, it is half the value. My friends suggested that I should multiply by number of blades to calculate the power from moment value?
Is it so?

ghost82 · November 16, 2013, 08:35

Hi,
if you simulated the whole 3d model you have not to multiply by the number of blades; you have to multiply only if you do periodic simulations.

Daniele

er_ijaz · November 16, 2013, 19:04

Hi
I run two simulations one fo 7 m/s and another for 10 m/s. In both cases my power is half of the experimental.

I think I have a problem with direction of rotation. I have a doubt while using thumb rule, index finger should be pointed from inlet to the blade or the index figer should point from blade to inlet

November 16, 2013, 05:48	is it necessary to multiply by number of blades with moment to calculate the power?	#1
er_ijaz Member ijaz fazil Join Date: Apr 2013 Location: Singapore Posts: 73 Rep Power: 13	Hi I have done the simulation of wind turbine using MRF analyis. I have not done any symmetric analysis. I have done whole blade simluation. But when I calculated power, it is half the value. My friends suggested that I should multiply by number of blades to calculate the power from moment value? Is it so?

November 16, 2013, 19:04	Hi, then do u have an idea where i'm going wrong	#3
er_ijaz Member ijaz fazil Join Date: Apr 2013 Location: Singapore Posts: 73 Rep Power: 13	Hi I run two simulations one fo 7 m/s and another for 10 m/s. In both cases my power is half of the experimental. I think I have a problem with direction of rotation. I have a doubt while using thumb rule, index finger should be pointed from inlet to the blade or the index figer should point from blade to inlet

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November 16, 2013, 08:35		#2
ghost82 Senior Member Rick Join Date: Oct 2010 Posts: 1,016 Rep Power: 26	Hi, if you simulated the whole 3d model you have not to multiply by the number of blades; you have to multiply only if you do periodic simulations. Daniele