Hi all,

Any idea about how to solve this problem?

Consider a cylinder fitted with a piston which contains saturated Steam at 30°C with 80% quality.

Let this vapor be compresses in a reversible adiabatic process until the pressure is 10 bars in

superheated conditions .Determine the work per kilogram of the steam for this process. Assume the

system is open system

I would start by looking at steam tables I think.

Many thanks

I am a little bit confused with the wording in question "Assume the system is open system" because the piston-cylinder arrangement is considered a closed system.

Sorry, that must be a typo, we must assume closed system

Hi,

Yes, start with the "saturated water-temperature" table and find h1 and s1 using the dryness fraction.

For reversible adiabatic process, s1=s2.

Now go into the superheated steam table for 1 MPa (10 bar) and get h2 by searching for the s1=s2 value. [You will need to interpolate].

work done per kg = h2 - h1

Let me know if you get stuck.