Chapter 7, Problem 7.21P

Plot the processes described on a PV diagram. Properly label the state points 1, 2, 3 ... and so on toindicate the correct sequence of the described changes in state.

A rigid, insulated vessel is divided into two compartments connected by a valve. Initially, one compartment, occupying 1.0 ft, contains air at 50 lb/in?, 750°R, and the other, occupying 2.0 ft?, is evacuated. The valve is opened and the air is allowed to fill both volumes. Assume the air behaves as an ideal gas and that the final state is in equilibrium. Determine the final temperature of the air, in °R, and the amount of entropy produced, in Btu/°R.

A vertical cylinder is fitted with a freely-moveable piston of 0.2 m diameter and contains 0.1 kg of (liquid) water. At the initial State 1, the water remains in equilibrium as saturated liquid at 15 "C with the piston applying a pressure of 7.0 bar on the water in the cylinder. The water is then slowly heated until the piston rises to a height of 0.6 m above its initial position to reach the equiliorium at State 2. The piston is now held fixed at this location and the cylinder contents are further heated to increase its pressure to 15 bar at State 3. (a) Find the volume of water at State 1. (b) Show that the cylinder contains saturated (wet) steam at State 2 and determine its dryness fraction at this state. (c) Find the steam temperature at State 3. On a T-v diagram, indicate the process undergone by the contents of the cylinder from State 1 to State 3.

Oxygen (O2) is contained within a horizontal piston-cylinder system initially O2 at 500 kPa, 200°C, and occupies a volume of 0.04 m². The gas expands according to the process described by pV!.15 = Constant, until the temperature reaches 97°C. Considering oxygen as an ideal gas and taking the specific heat of oxygen as constant at an average temperature between two states, a) Determine the final pressure (in kPa) and volume (m³). b) Determine the amount of work and heat transfer during the process, in kJ. c) Find the entropy production in this process (in kJ/K) if the boundary temperature is taken as 350°C. d) Write down the main sources of irreversibilities. e) Draw the processes on P-v and T-s diagrams.

A rigid, insulated vessel is divided into two compartments connected by a valve. Initially, one compartment, occupying 1.0 ft3, contains air at 50 Ib/in², 725°R, and the other, occupying 2.0 ft, is evacuated. The valve is opened and the air is allowed to fill both volumes. Assume the air behaves as an ideal gas and that the final state is in equilibrium. Determine the final temperature of the air, in °R, and the amount of entropy produced, in Btu/°R.

For each case, determine the specified property value and locate the state sketches of the p–υ and T–υ diagrams. For Refrigerant 134a at T = 160°F, h = 127.7 Btu/lb. Find υ, in ft3/lb. For Refrigerant 134a at T = 90°F, u = 72.71 Btu/lb. Find h, in Btu/lb. For ammonia at T = 160°F, p = 60 lbf/in.2 Find u, in Btu/lb. For ammonia at T = 0°F, p = 35 lbf/in.2 Find u, in Btu/lb. For Refrigerant 22 at p = 350 lbf/in.2, T = 350°F. Find u, in Btu/lb.

Parts ,g,h,i,j

Q5/ Determine the molar volume of butane at 510 K and 25 bar by each of the following : a- Ideal gas law. b- Compressibility factor.

A two-phase liquid–vapor mixture of H2O with an initial quality of 25% is contained in a piston–cylinder assembly as shown in figure. The mass of the piston is 40 kg, and its diameter is 10 cm. The atmospheric pressure of the surroundings is 1 bar. The initial and final positions of the piston are shown on the diagram. As the water is heated, the pressure inside the cylinder remains constant until the piston hits the stops. Heat transfer to the water continues until its pressure is 3 bar. Friction between the piston and the cylinder wall is negligible. Determine the total amount of heat transfer, in J. Let g  9.81 m/s2.