How are the mass flux and mass flow rate defined?
 

I am confused about the term 'mass flux' and 'mass flow rate'. It seems that they are same and they both can be used as' cell mass flux' and 'cell mass flow'.

Re: How are the mass flux and mass flow rate defin
 

The terms themselves are simple enough: "mass flux" is defined as "mass flow rate" per unit area. Maybe their use in this particular CFD code is confusing or wrong.

Re: How are the mass flux and mass flow rate defin
 

But how can I know the cell surface area? One cell has not only one surface. In the nom.inc, which one is the cell surface that is facing outside? I need to use the surface to calculate the mass flow rate with the density and velocity.