LES Turbulent Heat Transfer

For LES models, the definition of the filtered heat flux in the energy equation is based on a Boussinesq approximation, where the heat flux is assumed to be proportional to the subgrid scale viscosity.

The filtered heat flux $\tilde{q}$ in the energy equation Eqn. (1385) is defined as:

where:

• $\kappa$ is the thermal conductivity of the fluid.
• ${\mu }_t$ is the subgrid scale viscosity as given by the respective subgrid scale model.
• $C_p$ is the specific heat.
• ${\mathrm{Pr}}_t$ is the turbulent Prandtl number.
• $\tilde{T}$ is the filtered temperature.