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ldb83 June 25, 2013 21:47

Drag and lift coefficient for hydrofoil
 
5 Attachment(s)
Hello

I am studying oscillating hydrofoil in water.

I have used k-e model and the frequency and amplitude of hydrofoil are 1.25Hz and 1.0m.

Also I used PISO for solution method.
time step is 0.001s and number of time step is 800.

and when I checked the drag coefficient, the values are between 10000~-80000.

Originally, I have expected the value near 1.0.

I am wondering I have made some mistake in my model or the values are true?

Is there any one who could give me valuable comment?

Have a nice day all~

sadjad.s June 28, 2013 16:27

Answer
 
Hi mate,
Did you revise "Referece Values"?

ldb83 July 2, 2013 01:58

1 Attachment(s)
Quote:

Originally Posted by sadjad.s (Post 436636)
Hi mate,
Did you revise "Referece Values"?

Hi

When I review my reference value, I can't find any strange point.

sadjad.s July 2, 2013 03:03

Answer
 
It seems that you left default values and that's the problem.
What indicated in Reference values are just used in calculation of some Dimensionless numbers such as Drag and Lift coefficients.
As an example, for drag coefficient, you should revise Velocity, area and density.

ldb83 July 2, 2013 03:17

Quote:

Originally Posted by sadjad.s (Post 437222)
It seems that you left default values and that's the problem.
What indicated in Reference values are just used in calculation of some Dimensionless numbers such as Drag and Lift coefficients.
As an example, for drag coefficient, you should revise Velocity, area and density.


Thank you so much for your kind reply.

I will modify the reference value based on the my study.

Your comment is very helpful for me.

Have a nice day~


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