Field Function shows an error

niazaliahmed · September 23, 2011, 02:42

I am trying to write a vector field function to calculate 17/(Velocity^2)

I have tried

17/(pow($$Velocity,2))
17/($$Velocity*$$Velocity)

Both have failed. Is this because vector division is not possible, or some other error?

However when I use a single dollar Velocity it shows assembly code.

Please help me asap.

jfcorbett · September 23, 2011, 04:12

There is no such thing as vector division.

I'm guessing you want to divide by the magnitude of the velocity vector? STAR-CCM+ provides two ways to calculate the magnitude of a vector:

vector magnitude: mag($$u)
vector magnitude squared: mag2($$u)

So for you, the most straightforward expression is: 17/mag2($$Velocity)

For more, see STAR-CCM+ help:
Using Tools > Using Field Functions > Field Function Programming Reference > Vector Functions

niazaliahmed · September 23, 2011, 08:17

@jfcorbett
Thank you very much. The problem is solved now.

September 23, 2011, 02:42	Field Function shows an error	#1
niazaliahmed New Member Niaz Ali Ahmed Join Date: Jun 2010 Posts: 14 Rep Power: 15	I am trying to write a vector field function to calculate 17/(Velocity^2) I have tried 17/(pow($$Velocity,2)) 17/($$Velocity*$$Velocity) Both have failed. Is this because vector division is not possible, or some other error? However when I use a single dollar Velocity it shows assembly code. Please help me asap.

September 23, 2011, 04:12		#2
jfcorbett New Member Jean-François Corbett Join Date: Aug 2011 Posts: 8 Rep Power: 14	There is no such thing as vector division. I'm guessing you want to divide by the magnitude of the velocity vector? STAR-CCM+ provides two ways to calculate the magnitude of a vector: vector magnitude: mag($$u) vector magnitude squared: mag2($$u) So for you, the most straightforward expression is: 17/mag2($$Velocity) For more, see STAR-CCM+ help: Using Tools > Using Field Functions > Field Function Programming Reference > Vector Functions siara817 and Paola like this.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
polynomial thermophysical properties II	sebastian	OpenFOAM Running, Solving & CFD	54	November 21, 2019 07:12
[swak4Foam] GroovyBC the dynamic cousin of funkySetFields that lives on the suburb of the mesh	gschaider	OpenFOAM Community Contributions	300	October 29, 2014 18:00
How to install CGNS under windows xp?	lzgwhy	Main CFD Forum	1	January 11, 2011 18:44
checking the system setup and Qt version	vivek070176	OpenFOAM Installation	22	June 1, 2010 12:34
[swak4Foam] groovyBC: problems compiling: "flex: not found" and "undefined reference to ..."	sega	OpenFOAM Community Contributions	12	February 17, 2010 09:30

September 23, 2011, 08:17		#3
niazaliahmed New Member Niaz Ali Ahmed Join Date: Jun 2010 Posts: 14 Rep Power: 15	@jfcorbett Thank you very much. The problem is solved now.