Open System
In an open system mass and energy (in the form of heat and work) both can transfer across the boundary. Most of the engineering devices are open systems. (Refer Figure 1)
Examples: Boiler, Turbine, Compressor, Pump, I.C. Engine, etc.
Closed System
A closed system can exchange energy in the form of heat and work with its surroundings but there is no mass transfer across the system boundary. (Refer Figure 2)
The mass within the system remains constant however its volume can change against a flexible boundary. Further, the physical nature and chemical composition of the mass may change.
Examples: Cylinder bounded by a piston with a certain quantity of fluid, Pressure cooker and Bomb calorimeter, etc.
Isolated System
There is no interaction between the system and surroundings. (Refer Figure 3)
It is of fixed mass and energy, and hence there is no mass and energy transfer across the system boundary.
Examples: The Universe and Perfectly insulated closed vessel (Thermo flask) etc.
