In thermodynamics, a closed system, as contrasted with an isolated system, can exchange heat and work, but not matter, with its surroundings. Here, it is assumed that a thermally isolated (insulated) system can be realized. It is a useful idealization, even if it can only be asymptotically approximated. Thermodynamics (from the Greek thermos meaning heat and dynamis meaning power) is a branch of physics that studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale by analyzing the collective motion of their particles using statistics. ... A physical system is said to be isolated if it does not interact with anything. ... In physics, heat is defined as energy in transit. ... Work (abbreviated W) is the energy transferred by a force to a moving object. ... Matter is commonly defined as the substance of which physical objects are composed. ... An asymptote is a straight or curved line which a curve will approach arbitrarily closely, but never touch. ...
See also
Dynamical system: Has components and/or flows that change over time.
Open system: Can be influenced by events outside of the actual or conceptual boundaries.
In engineering terms, the "closedsystem" is actually two interrelated systems: a completely sealed system for recirculation water and a chiller or heat exchanger used to cool or remove heat from it.
Basically, heat is transferred to the closed loop by typical heat exchange equipment and is removed from the closedsystem by an exchange of heat from the closed loop to a secondary cooling water cycle.
The system is made continuous by compressing vaporized refrigerant, sending it to the condenser to be reliquified and then storing it in a receiver until it is released through an expansion valve for repeated duty to the chiller.
Such systems are scientifically interesting and can potentially serve as a life support system during space flights, at space stations or in submarines.
Perhaps confusingly, a closed ecological system is not a closedsystem in the usual sense, because energy (especially light and heat) is able to enter and leave the system, provided matter does not.
While both chemotrophic and phototrophic organisms are plausible, almost all closed ecological systems to date are based on a phototroph such as green algae.
Feeds |
Contact