UDF divergence of a vector

cris

i am working with the eulerian model and I would like to add a new term in the dispersed phase momentum equation. I can add easy terms using the macro DEFINE_SOURCE but i need the divergence of a vector. I made some easy probes to calculate the divergence of vector but i didn't suceed. Is there any macro to calculate the divergence of a vector? Is there anyone who has made a udf to calculate the divergence? I created some udf that use the divergence theorema to calculate the volume of a cell and the result is good, but when i tried to probe the udf in the steady state continuity equation the udf failed. If theres is someone interested i would send him my udfs. Sorry I am a spanish girl and i explain the best i could.