[Rui_27]

Hello everyone,

I would like to set a UDF function to specify a specie mass fraction at a wall of my computation domain using the DEFINE_PROFILE macro.

I use the value of the specie mass fraction at the adjacent cell next to the wall (C in the equation below) to calculate the value of x through:

x = A[(C-xD)/B] exp [E (F-Gx)] (equation 1)

where A,B,C,D,E,F and G are constants.

Then the value of x is used to calculate the specie mass transfer at the wall:

Mass fraction at the wall = f(x) (equation 2)

As you can see, equation 1 is in the implicit form (x cannot be isolated, at least I cannot do it). So how can I solve this implicit equation to obtain the value of x?

Thank you in advanced!