GAS
This monitored volume is typically used to model tire pressure or simple fuel tank.
For tire model V_{i} is zero and for fuel tank V_{i} is the fuel volume.
/MONVOL/GAS Examples
 A tire model: The inputs are:
 $\gamma $ = 1.4
 $\mu $
 ${P}_{ext}$ = 10^{5} Pa

${P}_{ini}$
= initial tire pressure
Then, the pressure in the tire is ${P}_{tire}={P}_{ini}{P}_{ext}$
 ${V}_{inc}=0$
 A fuel tank model if the sloshing effect is neglected Only if the sloshing effect is neglected, pressure in a partial filled fuel tank can be modeled with a type GAS monitored volume. Use the following input:
 $\gamma $ = 1.4
 $\mu $
 ${P}_{ext}$ = 10^{5} Pa
 ${P}_{ini}$ = 10^{5} Pa
 ${V}_{inc}$ = volume of fuel