View source for Transient state

{{short description|State of a system after conditions are changed, before it settles into steady state}}
{{more citations needed|date=January 2021}} 

In [[systems theory]], a [[system]] is said to be '''transient''' or in a '''transient state''' when a [[process variable]] or variables have been changed and the system has not yet reached a [[steady state]]. In [[electrical engineering]], the time taken for an [[electronic circuit]] to change from one steady state to another steady state is called the '''transient time.'''

==Examples==
===Chemical Engineering===
When a [[chemical reactor]] is being brought into operation, the concentrations, temperatures, species compositions, and reaction rates are changing with time until operation reaches its nominal process variables.

===Electrical engineering ===
When a [[switch]] is closed in an electrical circuit containing a [[capacitor]] or [[inductor]], the component draws out the resulting change in voltage or current, causing the system to take a substantial amount of time to reach a new [[steady state (electronics)|steady state]]. This period of time is known as the transient state.

A capacitor acts as a [[short circuit]] immediately after the switch is closed, increasing its [[Electrical impedance|impedance]] during the transient state until it acts as an open circuit in its steady state.

An inductor is the opposite, behaving as an open circuit until reaching a short circuit steady state.

==See also==
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*[[Attractor]]
*[[Carrying capacity]]
*[[Control theory]]
*[[Dynamical system]]
*[[Ecological footprint]]
*[[Economic growth]]
*[[Engine test stand]]
*[[Equilibrium point]]
*[[List of types of equilibrium]]
*[[Evolutionary economics]]
*[[Growth curve (statistics)|Growth curve]]
*[[Herman Daly]]
*[[Homeostasis]]
*[[Lead-lag compensator]]
*[[Limit cycle]]
*[[Limits to Growth]]
*[[Population dynamics]]
*[[Race condition]]
*[[Simulation]]
*[[State function]]
*[[Steady state]]
*[[Steady state economy]]
*[[Steady State theory]]
*[[Systems theory]]
*[[Thermodynamic equilibrium]]
*[[Transient modelling]]
*[[Transient response]]
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==References==
{{Reflist}}
<references group="https://ccrma.stanford.edu/~jos/fp/Transient_Response_Steady_State.html" />

[[Category:Chemical process engineering]]
[[Category:Electrical engineering]]
[[Category:Systems theory]]
[[Category:Control theory]]


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