An oil pump operating at steady state delivers oil at a rate of 12 Ib/s through a 1-in-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 70 Ib/ft³ and experiences a pressure rise from inlet to exit of 40 lb:/in?. There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp.

Q A horizontal piston-cylinder assembly contains 2.00 kg of a fluid. The assembly is fitted with both a heater and a paddle wheel. It is found that the fluid undergoes an expansion from state 1 to state 2. During the process, the paddle wheel transmits 16.4 kJ of mechanical energy (Wp.w.) to the fluid via mixing, and the heater supplies 83 kJ of thermal energy (Q) to the fluid. The specific internal energy changes from U1 = 2386.6 kJ/kg to U2 = 2409.1 kJ/kg during the process. Determine the work done by the steam on the piston during the process (Wpiston) (kJ). Your Answer: 45°F hp Insert * 24 % 8. 4 R H J K D F CV B N M

Steam generators are a type of heat exchanges that are used in power plants to generate steam at desired pressure and temperature (Fig. Q1.b). In a steam generator, saturated liquid water at 30°C enters a 60-mm diameter tube at the volume flow rate of 12 L/s. After exchanging heat with hot gas, the water changes to steam and leaves the generator at a pressure of 9 MPa and a temperature of 400°C. During this process, the diameter of the water/steam tube does not change.(iii) What is the exit velocity of the steam?

3. A hydraulic lift is shown below. The combined mass of the piston, rack, and car is 4000 lbm. The working fluid is water. There is no heat transfer to or from the water, and the internal energy of the water per unit mass is constant. The water may be considered incompressible. (a) Taking all the water in the reservoir, line, and hydraulic cylinder as the system (i.e., taking the closed-system approach), calculate the work necessary to raise the rack and car 1 ft (neglect the change in potential energy of the water in the system). (b) Repeat part (a), taking all the water plus the car and the rack as the system. (c) Repeat part (a), taking an open-system approach; choose as your system the volume of the hydraulic cylinder, excluding the piston, rack, and car. If the absolute pressure in the system is 1000 lbf/in², calculate the volume that must flow in to raise the car 1 ft. Reservoir Pump Hydraulic cylinder

H₂O Po 4.23 Two kilograms of water are contained in a piston/cylinder (Fig. P4.23) with a massless piston loaded with a linear spring and the outside atmosphere. Initially the spring force is zero and P₁ = P₁ = 100 kPa with a volume of 0.2 m³. If the piston just hits the upper stops the volume is 0.8 m³ and T = 600°C. Heat is now added until the pressure reaches 1.2 MPa. Find the final temperature, show the P-V dia- gram and find the work done during the process.

An oil pump operating at steady state delivers oil at a rate of 10 lb/s through a 1-in.-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 70 lb/ft3 and experiences a pressure rise from inlet to exit of 40 lb/in². There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp. Determine the power required for the pump, in hp.

A fixed-mass system contains mass, m = 1.0 kg of air. A thermodynamic process occurs from state one to state two, where T₁ = 300 °K, P₁ = 100 kPa; T₂ = 2700 °K, P₂ = 204.9953251 kPa. Determine S₂ - S₁ = m (S₂-S₁) in kJ / °K. Note: You are required to assume constant specific heats in this problem, with Cpo = 1.004 kJ/(°K * kg); for air, the gas constant is R = 0.287 kJ/(°K * kg).

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5. (a) There is 1000 kg water in a swimming pool. Consider the liquid water as an incompressible model at room temperature. If the temperature of the water body is increased by 3 degrees C (assuming this temperature change is uniform across the entire pool), determine: (i) the total internal energy change of the water, (ii) the total enthalpy change of the water. Use a constant heat capacity of water c = 4.211 kJ/kg. K. (b) In a big closed room, there is 1000 kg of air. Suppose the air is an ideal gas model at room temperature. The temperature of the room is increased by 3 degrees C heated by an electric heater. Suppose this temperature change is uniform across the entire room. (iii) Determine the total internal energy change of the air. (iv) Determine the total enthalpy change of the air. Use constant heat capacities of air c₂ = 0.718 kJ/kg . K and Cp = 1.005 kJ/kg.K.