CFD Online Discussion Forums

CFD Online Discussion Forums (
-   CFX (
-   -   Problem with source cfx (

TallesC March 6, 2013 20:53

Problem with source cfx
The problem below is informed:

Expression resolves to invalid units ('kg m^-3 s^-1') in value set for parameter 'Total Source' in object '/FLOW:Flow Analysi1/DOMAIN:serpentina/BOUNDARY:out serpentina/BOUNDARY SOURCE/SOURCES/EQUATION SOURCE:C2H3Cl'. Expected units: 'kg s^-1'.

how could resolved this problem??

evcelica March 6, 2013 22:57

Um . . . divide by m^-3 . . . . really?

TallesC March 6, 2013 23:10

I did not, how exactly do I do this?

evcelica March 7, 2013 05:29

Your expression has the wrong units. You are giving it a concentration per second, and it is expecting a mass per second. Fix your expression so that it gives the expected units.

ghorrocks March 7, 2013 05:41

barney=1[kg s^-1]

Now fred is in kg m^-3 s^-1

But even better - Erik's suggestion is that this means the expression calculating it is probably wrong. If the units do not check out the numbers have no hope of being right so dividing by m^-3 is not going to fix the real error.

TallesC March 7, 2013 08:51

Problem i'm creating a subdomain...before a try ina a boundary...thanks a lot!!1

All times are GMT -4. The time now is 02:33.