Write a fvc::Xxx function to do a vol to surface field calculation
 

Hi,

I want to write a explicit Filed operating function. It calculates as surfaceScalar Field from a volScalarField.

The input parameters are :

volScalarField vf;
dimensionedVector d; // a distance smaller than cell size

The output field is :

volScalarField vs;

The calculation procedure is:

For each cell face center x_s: vs(x_s) = vf(x_s - d),
as d is small enough, x_s - d is located in one of the neighbor cell of the cell face, say cell N.
The vf field value at (x_s -d) is interpolated from the center of cell N.

What is simplest way to write this function?


Best,

Lianhua