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-   -   User Subroutine ----- sorent (http://www.cfd-online.com/Forums/cd-adapco/56889-user-subroutine-sorent.html)

conglin November 24, 2008 01:26

User Subroutine ----- sorent
 
In the head of soren subroutine, it says "This subroutine enables the user to specify a source term (per unit volume) for enthalpy in linearized form:

Source = S1P-S2P*T, (W/m3)".

Why the unit is "w/m3"? Shouldn't enthalpy be J/kg?What does "per unit volume" mean? Should I define enthalpy (H) as:

H = f(T)/ VOLP ?

VOLP-----volume of the cell (m3).


ab November 24, 2008 12:37

Re: User Subroutine ----- sorent
 
w/m3 is rate energy is added per unit volume (in this case a unit volume is a cubic meter). A watt is just one joule per second... using joules would have no meaning in a steady state simulation, because time in infinite.

conglin November 24, 2008 20:45

Re: User Subroutine ----- sorent
 
Thank you, ad. I very appreciate your answer.

In the letter,it said"using joules would have no meaning in a steady state simulation,because time in infinite." Do you mean that the sorent subroutine must be sued in a transient simulation?

"in this case a unit volume is a cubic meter", and "the case" mesns the example equation-----"Source = S1P-S2P*T" or all the expressions used in this subroutine? If answer is the latter, then should I difine the source as:

Source = H/VOLP = (S1P-S2P*T)/VOLP ?

H ----- enthalpy,

VOLP ----- volume of the cell in my mold.

Regards.

conglin



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