When your Ansys CFX model includes Lagrangian particles, you can include the effect of particles in the radiation model.

For a medium containing gray absorbing and emitting particles, the contribution of the particles to the transport equation for the incident radiation can be written as

(8–9)

where is the effective emission of the particles and is the effective absorption coefficient. These are defined as follows:

(8–10)

and

(8–11)

In Equation 8–10 and Equation 8–11, , , and are the emissivity, projected area, and temperature of particle . The summation is over particles in volume . These quantities are computed during particle tracking in Ansys CFX.

The projected area of particle is defined as

(8–12)

where is the diameter of the th particle.