Recent content by brk51

So, I'm trying to bring it all together. I use enthalpies for saturated vapor because I can use the constant entropy value to find corresponding enthalpy values in the superheated water table, thus giving work input. My initial thought is that I can use vdP the same way I use it for item 1...

That's where I'm confused... are you saying there is another approach other than vdP to get the correct answer? The compressed water tables start out at a pressure of 5MPa

Yes that would be fantastic.. 1) I don't believe I assumed entropy was constant when looking up values, that is probably why I lost most points. I think I got the correct answers now, let me know what you get. However, on the exam I went to the Saturated Water - Pressure table and got values...

If I was to use the first law on the compressor Qin + mdot(h1) = Wout + mdot(h2) Control Volume so mass flow rate into compressor equals mass flow rate out>>> Cancels the mdots. Then you are left with Qin + h1 = Wout + h2. Since there is heat exchange in the compressor you are left with Wout=...

I think my mistake is treating a compressor and pump as basically the same thing only that they differ in that pumps deal with liquids and compressors deal with vapors. (My professor told us that)

I'm looking at my book right now. This is from the rankine cycle description.. : "1-2 isentropic compression in a pump. W_pump,in = h2-h1 or v(p2-p1)"

I'm considering the compressor to be a control volume so i use vdP

Homework Statement Compare the compressor work input required to compress water isentropically from 100kpa to 1MPa, assuming that the water exists as (a) saturated liquid and (b) saturated vapor at the inlet state Homework Equations Win = v(P2-P1) Win = (h2- h1) The Attempt at a Solution...

Apologize wifi in the library is not too hot, yes I get that.

yessir

Ok yes..

ther Are we talking about the problem I posted above or the literal derivation of the shear modulus

the book the book just uses variables but yes essentially continue..

ok thank you

While I understand your advice, that's why I'm here. I don't get it. I wouldn't just go through all this trouble posting a thread if I didn't already try to understand this.