Entropy in an irreversible process

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Entropy change for a closed system in an irreversible process cannot be zero; it is always greater than zero. An adiabatic process, which involves no heat transfer, still generates entropy due to irreversible effects like friction. The presence of irreversibility necessitates work to return the system to its initial state. Entropy generation serves as a measure of irreversibility in thermodynamic processes. Therefore, the concept of zero entropy change in irreversible processes is incorrect.
supermesh
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Can entropy change be zero for a closed system in an irreversible process? If yes under what conditions? Thanks!
 
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Is it true that entropy change for the irreversible process would be zero for an adiabatic process carried out in constant temperature?
 
No!
Adiabatic means no heat transfer. The fact that the process is irreversible means that there is still entropy generated however this is now due to friction or other irreversible effects
 
Hi there:

For an irreversible process, entropy change is always greater than zero.

It means that work needs to be provided in order to get the system back to its initial conditions.

By definition, entropy generation/increase/change is a measure of irreveribility ...

Thanks,

Gordan
 

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