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Old   May 20, 2014, 03:23
Default Writing Equation
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Dear Friends,

I have to calculate an expression which includes a term as written below:

|Ui-Vi|

Where Ui and Vi are velocity vectors of gas and particles.

Could you plz suggest me how to write these vectors in expression.
In results I found velocities in x, y and z direction available in drop down list.

Thanks
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Old   May 20, 2014, 03:37
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Matthias Voß
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Subtract each component and save them in an Expression
myVelU = Fluid.Velocity u - Gas.Velocity u
myVelV =...
myVelW=...
and create a User Variable Vector from these 3 components.

Or you can skip the variable and apply the norm directly to you expression like
myVelNorm = sqrt((myVelU)^2 +....)
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Old   May 20, 2014, 03:54
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Quote:
Originally Posted by mvoss View Post
Subtract each component and save them in an Expression
myVelU = Fluid.Velocity u - Gas.Velocity u
myVelV =...
myVelW=...
and create a User Variable Vector from these 3 components.

Or you can skip the variable and apply the norm directly to you expression like
myVelNorm = sqrt((myVelU)^2 +....)

Dear Matthias,

Thank you for the reply, I will follow this:

"myVelNorm = sqrt((myVelU)^2 +....)"

At the same time could you plz suggest me on how to create a User Variable Vector?


Regards
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Old   May 20, 2014, 04:00
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Matthias Voß
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In CFD-Post--> click on Create Variable (little alpha) and select vector instead of scalar.
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Old   May 20, 2014, 04:04
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Quote:
Originally Posted by mvoss View Post
In CFD-Post--> click on Create Variable (little alpha) and select vector instead of scalar.

Thank you again Matthias, its great.
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