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Urmi Roy

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Hi all,

I've been doing some pretty complex problems on closed systems in thermodynamics, and a few questions pooped up in my mind about Sgen (entropy generation). Please help me out with them..

1. When work is done on a system (like a paddle wheel in a cylinder containing gas), there is

3.

Thanks!

-Urmi

I've been doing some pretty complex problems on closed systems in thermodynamics, and a few questions pooped up in my mind about Sgen (entropy generation). Please help me out with them..

1. When work is done on a system (like a paddle wheel in a cylinder containing gas), there is

**no entropy 'transfer' but is Sgen non zero?**Then the 'entropy change' that we get from the constitutive relations for entropy change is wholly Sgen?**An interesting example of this an adiabatic process, where an insulated piston-cylinder system experiences work from outside, and the gas is compressed.**

2. Is quasi-static equivalent to reversible? Is Sgen zero for quasi-static/reversible process?3.

**Under what circumstances is it safe to assume entropy generation is 0**? I usually assume so when there is heat transfer between 2 objects that have**very different thermal conductivity or hear capacities.**..is that ok? Is there any additional situation?Thanks!

-Urmi

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