Definition - What does Closed System mean?
A Closed System is a system that does not allow any transfer of mass in or out of the system. The concept of closed systems comes from the branch of physics known as thermodynamics, which studies transfer of heat energy between objects and their environmental surroundings. Heat energy can also be exchanged within an object with its surroundings in a Closed System.
Petropedia explains Closed System
Systems are typically classified in three ways, i.e., open, closed and isolated systems.
In an open system, the energy and matter can enter or leave the system. Thus, this system interacts with the environment very well, i.e., it takes the input and delivers the output. Because of this reason, the objects that follow an open system, can quickly adopt to environmental changes. The perfect example of an open system is the Earth.
In a Closed System, the matter is not allowed to interact with the external environment, however if two bodies lie within a closed system, they can exchange heat energies. These systems are widely used in refineries and other industrial processing plants because they are helpful in conducting chemical reactions. A sealed chemical reactor can be considered as an example of a closed system.In an isolated system, neither energy nor matter is allowed to escape the boundary of the system. An example of an isolated system is space.