Hy everyone. I am using Fluent 6.1 and i try to modelise a plasma reactor. I am interested by the flow and chimical reactions modelling. In such a reactor some volumetric chemical reactions take place only in a particular volume of the reactor. I want to modelize the entire reactor while taking into account these reactions just in a part of it. How can I do this?

I don't really know what a plasma reactor is, but it reminds me of an article that I read:

http://www.fluent.com/about/news/new...2v11i2/a15.htm

Hope this might help you out.

Thank you Andrew for your answer but this article consider that the chemical reactions take place in all the reactor. Actually I need to "tell" fluent that the chemical reactions take place only in a particular volume of modelized domain. I think one of the solution is to use User Defined Subroutines (UDS) but it seems that, in Fluent 6, UDS are not available. Thank you once again!

Ah, OK, right, UDF's (User defined fuctions) are definatly avaliable in fluent 6, as I am alot of other, far more competant, members of this forum use them all the time. Fluent 6 comes wiht a specific UDF manual. You can specify volumetric reaction rate and surface reaction rate any way you want using these subroutines. Get the manual and check out 4.3.14 DEFINE_VR_RATE.

good luck

Razvan:

The zone of interest within the reactor needs to be singled out within the model. The cells of interest and the particular chemical reaction need to be specified within a subroutine. You need to define all the i, j, k locations and ranges within the model. I am not aware that you can do this with an UDF. I know that you could compile the subroutine made in Fortran or C and have Fluent execute after your compilation. A special way of starting Fluent is needed. For this you need the help of your local Fluent advisor and have all the computer-software tools to do it.

Francisco

I haven't done this in a while, so I had to check back over the manual. The function is passed values of the cell and cell thread as arguments, so if you want to create a reaction on a particular section of the cell thread simply put in a conditional clause based on the cell's geometrical loaction. You do not need to include a cell loop by the looks of things - so the funciton must be called with a cell loop in Fluent.