Adiabatic (from ''Gr.'' ἀ ''negative'' + διάβασις ''passage; transference'') refers to any process that occurs without

heat transfer Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, ...

. This concept is used in many areas of physics and engineering. Notable examples are listed below.

Automobiles

Engine braking Engine braking occurs when the retarding forces within an internal combustion engine are used to slow down a motor vehicle, as opposed to using additional external braking mechanisms such as friction brakes or magnetic brakes. The term is ofte ...

, a feature of some diesel engines, uses adiabatic expansion to diminish the vehicle's forward momentum.

Meteorology

Adiabatic lapse rate The lapse rate is the rate at which an atmospheric variable, normally temperature in Earth's atmosphere, falls with altitude. ''Lapse rate'' arises from the word ''lapse'' (in its "becoming less" sense, not its "interruption" sense). In dry air ...

, the change in air temperature with changing height, resulting from pressure change.

Quantum chemistry

* Adiabatic invariant

Born–Oppenheimer approximation In quantum chemistry and molecular physics, the Born–Oppenheimer (BO) approximation is the assumption that the wave functions of atomic nuclei and electrons in a molecule can be treated separately, based on the fact that the nuclei are much h ...

Thermodynamics

Adiabatic process An adiabatic process (''adiabatic'' ) is a type of thermodynamic process that occurs without transferring heat between the thermodynamic system and its Environment (systems), environment. Unlike an isothermal process, an adiabatic process transf ...

Adiabatic ionization Ionization or ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule i ...

Adiabatic index In thermal physics and thermodynamics, the heat capacity ratio, also known as the adiabatic index, the ratio of specific heats, or Laplace's coefficient, is the ratio of the heat capacity at constant pressure () to heat capacity at constant volu ...

Adiabatic accessibility In thermodynamics, adiabatic accessibility determines if one equilibrium state of a system can transition to another solely through an adiabatic process, meaning no heat is exchanged with the environment. The concept was coined by Constantin Carat ...

Quantum mechanics

Adiabatic theorem The adiabatic theorem is a concept in quantum mechanics. Its original form, due to Max Born and Vladimir Fock (1928), was stated as follows: :''A physical system remains in its instantaneous eigenstate if a given perturbation is acting on it sl ...

Adiabatic quantum motor An adiabatic quantum motor is a mechanical device, typically nanometric, driven by a flux of quantum particles and able to perform cyclic motions. The adjective “adiabatic” in this context refers to the limit when the dynamics of the mechanica ...

Electronics

Adiabatic circuit Adiabatic circuits are low-power electronic circuits which use " reversible logic" to conserve energy. The term " adiabatic" refers to an ideal thermodynamic process in which no heat or mass is exchanged with the surrounding environment, alludi ...

Adiabatic logic Adiabatic circuits are low-power electronic circuits which use " reversible logic" to conserve energy. The term " adiabatic" refers to an ideal thermodynamic process in which no heat or mass is exchanged with the surrounding environment, alludi ...

References

Thermodynamic processes Science-related lists {{DEFAULTSORT:Adiabatic concepts