expression in CFX POST

zryan civil · July 9, 2016, 13:26

Hello
I want to create expression to find Froude number (v/(gy)^0.5) at a certain location using line, from expression avgvelocity()@line1/(areaInt(water.vf)@line1/area()@line1)*g )^0.5 but it showed error. also I used the same expression for plane, the same problem occur
thanks for your help

ghorrocks · July 9, 2016, 21:22

Showing the error message might help.....

Note there is no function "avgvelocity()@line1".

zryan civil · July 10, 2016, 03:34

Quote:

Originally Posted by ghorrocks

Showing the error message might help.....

Note there is no function "avgvelocity()@line1".

now the expression contain, function variable and location but still it gives error if bracket and SQRT removed only error from (Velocity) other wise error occur in all term under root.
areaAve(Velocity)@line1/[(areaInt(Water.Volume Fraction)@line1/area()@line1)*g]^0.5
I used velocity same as in the CFX documentation

ghorrocks · July 10, 2016, 10:03

CEL does not use square brackets. They need to be normal brackets.

You cannot do areaInt() of a line object. Or maybe you can - but the answer is zero as it has no area. Likewise the area() of a line is zero as well.

You still have not posted the error message you are getting....

zryan civil · July 10, 2016, 12:47

Quote:

Originally Posted by ghorrocks

CEL does not use square brackets. They need to be normal brackets.

You cannot do areaInt() of a line object. Or maybe you can - but the answer is zero as it has no area. Likewise the area() of a line is zero as well.

You still have not posted the error message you are getting....

the follow error occur for line and plane
https://drive.google.com/open?id=0B3...HZWQWZzRkFHNHc
https://drive.google.com/open?id=0B3...1daaXlnZEQxRUU
thanks

ghorrocks · July 10, 2016, 20:25

The error message says exactly what the problem is. There is no variable called "Velocity", there is "U Velocity", "V Velocity" and "W Velocity", or the short version u, v, w.

zryan civil · July 11, 2016, 08:53

Quote:

Originally Posted by ghorrocks

The error message says exactly what the problem is. There is no variable called "Velocity", there is "U Velocity", "V Velocity" and "W Velocity", or the short version u, v, w.

I used U Velocity, and change bracket to normal the same error occur!!!
areaAve(U Velocity)@Plane 1/((areaInt(Water.Volume Fraction)@Plane 1/area()@Plane 1)*g)^0.5

ghorrocks · July 11, 2016, 09:48

Look in the CFX reference guide for the variable names. You need to get the variable names correct or it won't accept them. It is also case sensitive.

zryan civil · July 14, 2016, 08:23

Quote:

Originally Posted by ghorrocks

Look in the CFX reference guide for the variable names. You need to get the variable names correct or it won't accept them. It is also case sensitive.

thanks
I used the velocity variable as cited in CFX reference but same error happen, just for test I used pressure (p) it gives a result as in attached pictures.
thanks for your suggestion
https://drive.google.com/open?id=0B3...WNlcjVVTDA1Mzg
https://drive.google.com/open?id=0B3...VpQZUl1c29OZms

July 9, 2016, 13:26	expression in CFX POST	#1
zryan civil Member Join Date: May 2016 Posts: 40 Rep Power: 10	Hello I want to create expression to find Froude number (v/(gy)^0.5) at a certain location using line, from expression avgvelocity()@line1/(areaInt(water.vf)@line1/area()@line1)*g )^0.5 but it showed error. also I used the same expression for plane, the same problem occur thanks for your help

July 10, 2016, 10:03		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	CEL does not use square brackets. They need to be normal brackets. You cannot do areaInt() of a line object. Or maybe you can - but the answer is zero as it has no area. Likewise the area() of a line is zero as well. You still have not posted the error message you are getting.... Red Ember and zryan civil like this.

July 10, 2016, 20:25		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	The error message says exactly what the problem is. There is no variable called "Velocity", there is "U Velocity", "V Velocity" and "W Velocity", or the short version u, v, w. zryan civil likes this.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
export expression from CFX post	owarlow	CFX	5	November 12, 2019 17:43
writing execFlowFunctionObjects	immortality	OpenFOAM Post-Processing	30	September 15, 2013 07:16
Is it possible to obtain compressor map for axial compressor in CFX post ?	Irondome	CFX	1	June 16, 2013 07:24
How to install CGNS under windows xp?	lzgwhy	Main CFD Forum	1	January 11, 2011 19:44
CGNS lib and Fortran compiler	manaliac	Main CFD Forum	2	November 29, 2010 07:25

July 9, 2016, 21:22		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Showing the error message might help..... Note there is no function "avgvelocity()@line1".

July 11, 2016, 09:48		#8
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Look in the CFX reference guide for the variable names. You need to get the variable names correct or it won't accept them. It is also case sensitive.