[helly]

Hello foamers
I am simulating channel395 using pimplefoam (for LES simulation) and now I want to do postprocessing. I need to calculate second order structure function which is defined as:
<(del(u))**2> = <(u(x+del(x))-u(x))**2> (Davidson et al, Journal of fluid mechanics, 2006)

Here <> means averaged quantity and u is the streamwise velocity in x direction and I need to calculate this parameter for w(spanwise velocity) too. but I dont know how to calculate these parameters!!! I need to calculate them in special y (distance from wall) but if It will be possible to calculate them for all y it would be perfect.
I tried to change postchannel.C and foamCalc.C but it was not possible for me as I couldnt understand the commands. I am used to work with an in house code by fortran and use the loops like:
do i=1,x
do j=1,y
....
end do
end do

so I dont have any idea how to change these code or calculate these parameters, so I want to ask for help is anyone can help me.

Thanks in advance