Consider the cycle made of path A followed by path B shown below. |
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The following integrals have been evaluated. |
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Is this cycle reversible, irreversible or impossible? |
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Read : |
This is a
straightforward application of the Clausius Inequality to a thermodynamic cycle interacting with two thermal reservoirs. |
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Diagram: |
See the problem
statement. |
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Given: |
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-24.7 |
kJ/K |
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41.3 |
kJ/K |
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Find: |
Is this cycle reversible, irreversible or impossible? |
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Assumptions: |
None. |
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Equations
/ Data / Solve: |
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The Clausius Inequality is: |
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Eqn 1 |
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If the cyclic integral is … |
... positive, the
cycle is impossible |
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... negative, the
cycle is irreversible |
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... zero, the cycle is
reversible |
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Since the cycle is made up of two steps, A
& B, we can expand
Eqn 1 as follows: |
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Eqn 2 |
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Now, we can plug in
values from the problem statement. |
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16.6 |
kJ/K |
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Because the cyclic
integral is greater than zero, the cycle is impossible. |
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Verify: |
None. |
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Answers : |
Because the cyclic integral is greater than
zero, the cycle is impossible. |
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