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 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 often confused with sever ...
, 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 the sense of a gradual fall. In dry air, the adiabatic lapse rate is ...
, 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 best-known mathematical approximation in molecular dynamics. Specifically, it is the assumption that the wave functions of atomic nuclei and elect ...
Thermodynamics
*
Adiabatic process
In thermodynamics, an adiabatic process (Greek: ''adiábatos'', "impassable") is a type of thermodynamic process that occurs without transferring heat or mass between the thermodynamic system and its environment. Unlike an isothermal process, ...
*
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
Adiabatic accessibility denotes a certain relation between two equilibrium states of a thermodynamic system (or of different such systems). The concept was coined by Constantin Carathéodory in 1909 ("adiabatische Erreichbarkeit") and taken up 90 ...
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 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, allud ...
Carbohydrate chemistry
*
Adiabatic map
Extraction
*
Adiabatic extraction
Adiabatic Extraction process
/ref>
References
Thermodynamic processes
Science-related lists
{{DEFAULTSORT:Adiabatic concepts