wallHeatFlux and P1 radiation

Summary

When postProcessing with wallHeatFlux, P1 radiation heat flux is not added. So only the convective heat flux is calculated and saved in the field of "wallHeatFlux"

Steps to reproduce

Example case

What is the current bug behaviour?

WallHeatFlux function gives same heat flux in the cases without radiation and with P1 radiation

What is the expected correct behavior?

WallHeatFlux in the case with P1 radiation must be larger than WallHeatFlux in the case without radiation.

Relevant logs and/or images

Environment information

• OpenFOAM version : v1906
• Operating system : ubuntu
• Hardware info : Intel I7 PC
• Compiler : gcc

Possible fixes

The problem is from that in P1.C code read-option of qr is NO_READ. On the contrary in FvDOM.C read-option of qr is READ_IF_PRESENT. When the read-option of qr in P1.C code is changed to READ_IF_PRESENT, wallHeatFlux function gives the sum of convective and radiative heat flux.