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Old   February 16, 2015, 10:09
Default Cell size
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Hi all,
I am using fluent for my project and it's been very challenging as I am learning it myself with no one to guide me.

I have done my meshing using edge sizing and mapped face. I would like to know my cell size to enable me choose a good time step. Does anyone know how to get this info?

Thanks
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Old   February 16, 2015, 10:17
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You always need small enough cells to get spatially resolved information but if you want time-resolved simulations, then calculate your cell Courant number based on the time-step size that you want and expected cell velocity. Target Courant number ~1.
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Old   February 16, 2015, 13:08
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Thanks LuckyTran.

I finally set up my problem and monitor. I used a UDF to define my sinusoidal velocity. However, in the monitor at the inlet I get something like this
velocity monitor.JPG

I expected a sine profile but the above profile is only correct form wt = 0 - pi.
I'm posibly doing something wrong. Could someone kindly point me to the right direction.

Thanks.
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Old   February 16, 2015, 14:42
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Are you specifying the profile using magnitude and direction or components. I think you should be using x,y,z components.
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Old   February 16, 2015, 16:28
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I initially used magnitude and direction. I have now used components and hooked my udf in the inlet x component. I have also monitored the x component velocity close to the outlet and I can see a sine behaviour.

Thanks again luckyTran.
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