Question

A rigid tank with a volume of 4 m^3 contains argon at 500 kPa and 30 deg C. It is connected to a piston cylinder (initially empty) with a line and a closed valve. The pressure in the cylinder should be 300 kPa to float the piston. Now the valvle is slowly opened and heat is transferred so the argon reaches a final state of 30 deg C with the valve open. The heat transfer takes place from a 60 deg C space through a conduction layer 1 cm thick with a conductivity k = 0.1 W/mK and a surface area of 1.5 m^2.
a. Find the final volume of the argon and the total work for the process.

b. Find the total heat transfer needed.

c. How long will the process take?

Answer 1

Answer:

a) Final Volume: 6.667 m³, Total Work = 1.02175 MJ

b) Heat Transfer = 1.02175 MJ

c) Time: t = 37 min, 50.5 seconds (37.84 minutes OR 0.63 hours)

Explanation: