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Darcy March 7, 2001 06:07

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?

Sascha March 12, 2001 10:49

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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