[NickSD]

Hi

I have data about droplets formed in a spray from an injector and need to find a shape factor for it. The problem is that there's no way of tracking the droplets as I only have the data and not the original CFD. The reason is that the analysis that will be done following this requires the particles to be approximated as spheres meaning I need to see just how similar to a sphere the droplets are.

The values I have available to me are:

Timestep
Mass
#Cells (Trim)
Position (x,y,z)
Velocity (x,y,z)
Extents (x,y,z)

I'm effectively looking for as many ways as possible to characterise shape factor using only these values. I've already considered looking at the relative sizes of each of the droplets (possible, but doesn't take VoF/mass into account) as well as trying to calculate some sort of moment of inertia (this isn't feasible as there is no way of tracking the cells). I also cannot assume that cells are full as that assumes a shape factor already, which is what I want to work out.

Due to the volume of data, it would be nice if the calculation would be something that could easily be written in Fortran77 or C++.

Any help would be much appreciated.

Thanks