scalar advection-diffusion equation
 

Hello everybody

In the Solver-Manual of CFX-4.2, the Navier-Stokes equation is transformed to scalar advection-diffusion equations. I'm confused with the energy equation. How is the diffusion term defined in the energy equation? What is the scalar variable in energy equation? Enthalpy? or temperature?

Re: scalar advection-diffusion equation
 

The scalar in the energy equation is the specific enthalpy h. Therefore the diffusion coefficient is the heat conductivity lambda. By transfornation of the enthalpy equation to a temperature equation you will have the temperature diffusivity in the diffusion term.

The scalar advection-diffusion equation is teh general form for the PDE of NSE. So it is then a bit more easy to add yr own equation...

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