periodic boundary condition on long 3D trapezoidal enclosure
 

hey fluenter's

i simulating natural convection heat transfer in the 3D enclosure . (as show in picture )
i want to simulate it for long length . at first i use adiabatic condition for rear and front walls . but now i want to use periodic condition for rear and front walls .

any idea how i can do it ?

the TUI command to form a periodic pair is:

define boundary-conditions modify make-periodic

i know creation periodic boundary condition . i don't know setting and also difference between periodic and shadow .( i mean when choose periodic boundary , need define periodic and shadow, whats the difference ?)