Dear Sir;

if you mean a cellular or porous material, you can use BET, pycnometry, and microscope. The question is a little bit confusing, would you please give additional details. Regards

hello Mr. Bouaziz

in mcnp code we can define a cell with a certain material . but we may want to define some pores in the material and we want them to be random in size , shapes and positions . is there any way to do this ?

regards

Dear Behnam,

now I come to understand your task, you are looking for a sort of a modal to start with the Monte Carlo simulation, I have some books on the method and I will see if there is any kind of information. I was thinking about a laboratory experimental work. Regards

you can use the URAN Stochastic Geometry Card . I don't know how but I think  It may be useful to do that.