The values for the possible filling material of the duct are listed such as air, nitrogen at 15 bar, water and oil.

Symbol
$\sigma_{\mathrm{d_{\mathrm{fill}}}}$
Unit
J/K.m³
Related
$\sigma_{\mathrm{d}}$
Used in
$Q_{\mathrm{d_{\mathrm{fill}}}}$
Choices
MaterialValue
AirNormal air1200.0
N2Nitrogen at 15 bar17000.0
H2OCooling water4180000.0
OilMineral oil1700000.0