Hi I want to simulate a termal,batch reactor in fluentbut I don't know how use chemistry files to define polyethylene for prepdf,plz help me to complite my project thanks

U can use the chemical dile by going to define--->material--->database

then search the required chemical and click and add it on the list.

HI Thanks for your guid,but I konw this steps,I want to define materials that don't exsit in databaise and I should define with myself and I don't how can I define this parameters for fluent thanks if u help me

ok then us a material that is similar to the material u want to use but in the material panel change the properties ie specific heat, density, etc.