**What is the definition of Total heat transfer rate for Compressible fluid?**

When performing thermal calculations, check the heat balance in the total heat transfer rate [W] through Report->Fluxes. For an incompressible fluid, the definition is:

= ̇ × × ( − 298.15) [ ]

= ̇ × × ( − 298.15) [ ]

where,

̇: mass flow rate [kg/s]

Cp: specific heat [J/kg-K]

T: face temperature [K]

̇: mass flow rate [kg/s]

Cp: specific heat [J/kg-K]

T: face temperature [K]

However, in the case of a compressible fluid (density set to Ideal-gas), the definition differs between the pressure and density-based solvers.

Please refer to this document for more information.