Unformatted text preview: MEEN 315‐501 Fall 2010 Problem Set 06 Due: Monday October 11, 2010, 13:50 1. One kilogram of air, initially at 5 bar, 350 K, and 3kg of carbon dioxide (CO2), initially at 2 bar, 450 K, are confined to opposite sides of a rigid, well‐insulated container, as illustrated in Fig. 1. The partition is free to move and allows conduction from one gas to the other without energy storage in the partition itself. The air and carbon dioxide each behave as ideal gases. Determine the final equilibrium temperature, in K, and the final pressure, in bar, assuming constant specific heats. Fig. 1 2. Helium (He) gas initially at 2 bar, 200 K undergoes a polytrophic process, with n = k, to a final pressure of 14 bar. Determine the work and heat transfer for the process, each in kJ per kg of helium. Assume ideal gas behavior. 3. Two uninsulated, rigid tanks contain air. Initially, tank A holds 1 lb of air at 1440ºR, and tank B has 2 lb of air at 900ºR. The initial pressure in each tank is 50 lbf/in2. A valve in the line connecting the two tanks is opened and the contents are allowed to mix. Eventually, the contents of the tanks come to equilibrium at the temperature of the surroundings, 520ºR. Assuming the ideal gas model, determine the amount of energy transfer by heat, in Btu, and the final pressure, in lbf/in2. 4. One lb of air undergoes a power cycle consisting of the following processes: Process 1~2: constant volume from p1=20 lbf/in2, T1=500ºR to T2=820ºR. Process 2~3: adiabatic expansion to v3 = 1.4v2 Process 3~1: constant‐pressure compression Sketch the cycle on a p‐v diagram. Assuming ideal gas behavior, determine the pressure at state 2, in lbf/in2. the temperature at state 3, in ºR. the thermal efficiency of the cycle. 5. 6. 7. 8. 9. ...
View Full Document
- Fall '07
- lbf/in2, 2 bar, final pressure, ideal gases. Determine