(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A gas enters a compressor and is compressed isentropically. Does the specific enthalpy (h) increase or decrease as the gas passes from inlet to exit?

2. Relevant equations

[tex]\left(\frac{\partial{h}}{\partial{p}} \right)_s= v\qquad(1)[/tex]

3. The attempt at a solution

Since the specific volumevis a positive number we know that pressure increases (since it is being compressed), then the enthalpy must also increase.

This is the answer that was given in the book. I don't really like it. The left side of (1) is a differential change and hence the right hand side is asingle value. When we extend this idea to a finite change, what happens to the right hand side?

Does anyone see what I mean by "I don't like it?" We are looking at values ofhandpat two different states 1 and 2. But what the heck isvsupposed to do?

I feel like to get the full story, we would need to integrate dh = v(p) dp. We know that v should decrease with an increase in p. Any thoughts?

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# Thermodynamic Relation

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