PARAM, SIGMA

Bulk Data Entry The Stefan-Boltzmann constant used in Radiation Heat Transfer calculations.

Parameter	Values	Description
`SIGMA`	< Real > Default = 0.0	The radiation heat flux is:(1) $q = σ \cdot FAMB \cdot (ε_{e} {(T_{e} + T_{a b s})}^{4} - α_{e} {(T_{a m b} + T_{a b s})}^{4})$ Where, $σ$ is the Stefan-Boltzmann constant (PARAM,SIGMA). The temperatures and SIGMA should be defined in consistent units. Based on the input temperature units, the absolute temperature scale factor, $T_{a b s}$ , can be defined via PARAM,TABS. The value of SIGMA in SI units is 5.67E-8 Watts/m²K⁴.

Parameter

Values

Description

SIGMA

< Real >

Default = 0.0

The radiation heat flux is:(1)

q = σ \cdot FAMB \cdot (ε_{e} {(T_{e} + T_{a b s})}^{4} - α_{e} {(T_{a m b} + T_{a b s})}^{4})

Where, $σ$ is the Stefan-Boltzmann constant (PARAM,SIGMA).

The temperatures and SIGMA should be defined in consistent units. Based on the input temperature units, the absolute temperature scale factor, $T_{a b s}$ , can be defined via PARAM,TABS. The value of SIGMA in SI units is 5.67E-8 Watts/m²K⁴.

Comments

If PARAM, SIGMA is not set, there is no heat transfer based on radiation in the model.