How to estimate the gas leakage

Gas leakage involves the release of gas from a containment system, whether it’s a pipe, or vessel. From a thermodynamic perspective, the process of gas leak can be understood through principles such as ideal gas law, thermodynamic equilibrium, and entropy (s).

Gas Thermodynamic Process

Isentropic (Adiabatic) Process

An isentropic process is one in which the entropy (s) of a system remains constant. In fact, gas leakage trends to increase entropy as the gas expands into a larger volume, resulting in a more disordered state since the entropy (s) is a measure or the disorder or randomness of a system.
In practical terms, an isentropic process is often an idealization of a process that occurs without any heat exchange with the surrounding environment. (Q = 0)
For an ideal gas undergoing an isentropic process, the relationship between pressure (P) and Volume (V) can be described as following;

For example, the isentropic process is the expansion of gas in a piston-cylinder.

Isothermal Process

An isothermal process is one that occurs at constant temperature.
In an isothermal process, the internal energy of the system remains constant (dU = 0), meaning that any heat added to or removed from the system is entirely converted into work (Q = -W)
For an ideal gas undergoing an isothermal process, the relationship between pressure (P) and volume (V) is described by the ideal gas law.

The example process of isothermal is a gas confined within a cylinder fitted with a movable piston. And to maintain the temperature, this cylinder shall be placed in a large water bath with provided temperature by heat sink.