5.72 As shown in Fig. P5.72, a heat pump provides energy by heat transfer to water vaporizing from saturated liquid to saturated vapor at a pressure of 2 bar and a mass flow rate of 0.05 kg/s. The heat pump receives energy by heat transfer from a pond at 16°C. These are the only significant heat transfers. Kinetic and potential energy effects can be ignored. A faded, hard-to-read data sheet indicates the power required by the heat pump at steady state is 35 kW. Can this value be correct? Explain. Saturated

5.72 As shown in Fig. P5.72, a heat pump provides energy by heat transfer to water vaporizing from saturated liquid to saturated vapor at a pressure of 2 bar and a mass flow rate of 0.05 kg/s. The heat pump receives energy by heat transfer from a pond at 16°C. These are the only significant heat transfers. Kinetic and potential energy effects can be ignored. A faded, hard-to-read data sheet indicates the power required by the heat pump at steady state is 35 kW. Can this value be correct? Explain. Saturated

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Assume 2.30 lb/sec of fluid enter a steady-state, steady-flow system with P₁ = 105.73 psia, P1 = 0.324 lb/ft³, v₁ = 92.08 fps, u₁ = 792.25 BTU/lb, and leave with P2 24.04 psia, p2 = 0.113 lb/ft³, v₂ = 484.46 fps, and u₂ = 761.10 BTU/lb. During the passage through the open system, each pour rejects 11.7 BTU of heat. Determine the work in hp.
Liquid flows at steady state at a rate of 2 lb/s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. The liquid specific enthalpy at the inlet is 40.09 Btu/lb and at the exit is 40.94 Btu/lb. The pump requires 3 Btu/s of power to operate. If kinetic energy effects are negligible and gravitational acceleration is 32.174 ft/s2, the heat transfer rate associated with this steady state process is most closely: A) 2.02 Btu/s from the liquid to the surroundings. B) 3.98 Btu/s from the surroundings to the liquid. C) 4.96 Btu/s from the surroundings to the liquid. D) 1.04 Btu/s from the liquid to the surroundings.
Three return steam lines in a chemical processing plant enter a collection tank operating at steady state at 9 bar. Steam enters inlet 1 with flow rate of 2 kg/s and quality of 0.9. Steam enters inlet 2 with flow rate of 2 kg/s at 200°C. Steam enters inlet 3 with flow rate of 1.2 kg/s at 95°C. Steam exits the tank at 9 bar. The rate of heat transfer from the collection tank is 40 kW.Neglecting kinetic and potential energy effects, determine for the steam exiting the tank:(a) the mass flow rate, in kg/s.(b) the temperature, in °C.
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Heat transfer through a temperature difference is irreversible,
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Steam enters the condenser of a vapor power plant at 0.60 bar with a quality of 0.90 and condensate exits at 0.60 bar and 33°C. Cooling water enters the condenser in a separate stream as a liquid at 24°C and exits as a liquid at 36°C with no change in pressure. Heat transfer from the outside of the condenser and changes in the kinetic and potential energies of the flowing streams can be ignored. For steady-state operation, determine the energy transfer from the condensing steam to the cooling water, in kJ per kg of steam passing through the condenser. Select one: a. -2900.16 kJ/kg b. -2105.36 kJ/kg c. -2285.81 kJ/kg d. 2276.70 kJ/kg