Types of Thermodynamic Systems

  • Open system: Mass and energy transfers across the boundary of the system.
    e.g.: Open vessel having a liquid.

  • Closed system: Energy transfers across the boundary of the system. No transfer of mass occurs.
    e.g.: A gas confined in a piston-cylinder arrangement, the walls of cylinder is a good thermal conductor.

  • Isolated system: No transfer of mass or energy across the boundary of the system.
    e.g.: A gas confined in a piston-cylinder arrangement, the walls of which are made of insulating materials.

The following tablegives the comparison of various systems.

Type of SystemMass FlowWorkHeat
Open\(\checkmark\)\(\checkmark\)\(\checkmark\)
Closed\(\boldsymbol\times\)\(\checkmark\)\(\checkmark\)
Isolated\(\boldsymbol\times\)\(\boldsymbol\times\)\(\boldsymbol\times\)