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== {{div col|colwidth=15em}} *[[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]] {{div col end}}

==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]]