[Shaheer]

I am working on a slightly complex model than a normal heat transfer model. I need some advice can any one please help me up a bit?
I have to model a straw not steel ie a composite material. I can get its thermal conductivity and so forth how do i define that ?
Second thing is the straw will be in contact with a steel particle having high temperature and the atmosphere is nitrogen.
Now i am sure atmosphere is not a problem since the ambient temperature and the film coefficent is all thats needed not the chemical composition of the atmosphere but i dont know how to model the 2 things together in ANSYS thermal with individual data. Can i custom feed their thermal conductivity and specific heat and so forth if i have two geometry?
Basically i want to see how a higher heat particle will effect the straw at low temperature.
Any one can help please?