isentropic process

isentropic process [¦īs·ən′träp·ik ′prä·ses]

(thermodynamics)

A change that takes place without any increase or decrease in entropy, such as a process which is both reversible and adiabatic.

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Isentropic process

In thermodynamics, a process involving change without any increase or decrease of entropy. Since the entropy always increases in a spontaneous process, one must consider reversible or quasistatic processes. During a reversible process the quantity of heat transferred is directly proportional to the system's entropy change. Systems which are thermally insulated from their surroundings undergo processes without any heat transfer; such processes are called adiabatic. Thus during an isentropic process there are no dissipative effects and the system neither absorbs nor gives off heat. For this reason the isentropic process is sometimes called the reversible adiabatic process. See Adiabatic process, Entropy, Thermodynamic processes