3d pemfc model - fluent module & gambit - error

meisam

I try with fluent pemfc modul and use tutorial ' modeling a single channel , counter flow pem fuel cell . 2007 fluent inc ' but i dont know what the problem is cauz after first iteration the error messge 'floating point error' will appear . I think maybe boundry condition/zones that present in gambit or mesh size are wrong , but i do exactly according to the tutorial .

1- Is anode/cathod side flow channel each one apply 3 faces & and 1face that remine apply with gdl or they have another definition ?

2- Is anode/cathod side diffusion layer each one apply 3 faces or 4 faces or they have another definition ?

example for 4 faces: (2 faces ... interface collector & gdl) (1 face ... interface anode/cathod & gdl) (1 face interface catalyst & gdl)

3- do u have idea , what is my mistake ?

i am thankfull if you have mesh or case file about and send for me .