Steam at 500°C and 600 kPa is throttled to 100 kPa. Determine the entropy generation (in...
Steam at 10 MPa, 600 'C is throttled to 1 MPa, and fed into an adiabatic mixing chamber where it is mixed with compressed liquid water at 1 MPa, 50 C. The exiting mass flow is 100 kg/s of saturated liquid at 1 MPa. For steady state operation, determine a) te mass flows of steam and liquid that enter, b) the rate of entropy generation due to throttling, and the rate of entropy generation due to mixing, c) te associa...
Nitrogen is expanded from 2000 kPa and 500°C to 100 kPa and 50°C. Assuming constant specific heats, determine the change in the specific entropy of Nitrogen A. -0.0478 kJ/kgK B.-0.0175 kJ/kg C. 0.0175 kJ/kgK D. -1.503 kJ/kgK
#4. To operate a steam turbine in part-load output, a throttling valve is used as shown. The valve reduces the pressure of steam before it enters the turbine. The state of steam in the supply line remains fixed at 2 MPa, 500°C and the turbine exhaust pressure remains fixed at 10 kPa. Assuming the turbine to be adiabatic and reversible, determine (a)the full load specific work output in kJ/kg, (b)the pressure of the steam must be throttled to for 75%...
A saturated liquid–vapor mixture of water, in a pipe line at 1.5 MPa is throttled to 100 kPa and 150°C. Determine (a) the quality of the mixture (b) the entropy change during the throttling process.
Steam enters an adiabatic turbine steadily at 7 MPa, 500 °C, and 45 m/s, and leaves at 100 kPa and 75 m/s. If the power output of the turbine is 5 MW and the isentropic efficiency is 77 percent, determine: A. the mass flow rate of steam through the turbine, B. the temperature at the turbine exit, and C. the rate of entropy generation during this process.
An adiabatic tank, 0.5 m3, is initially evacuated and charged with steam at 500 kPa and 300 C. The final tank pressure is 500 kPa. Determine the final temperature and the entropy production. Answers: 461.5 C, 0.379
Question 11 A piston cylinder-device contains 12 kg of steam at 100 kPa and 175°C. Over time, the steam in the piston-cylinder device isobarically loses heat to its surroundings until it reaches a temperature of 99.61"C and all the vapor in the piston has condensed into liquid. a. Determine the entropy change of the steam, in kJ/K b. For the steam and its surroundings, determine the total entropy change associated with this process, in kJ/K. The temperature of the surroundings...
5. A 15 kg saturated steam has a pressure of 600 kPa and internal energy of 24,725 K. (a) Determine the quality of the saturated steam. (b) Determine the enthalpy of the saturated steam. 6. Air at 600 K flows with 3 kg/s into a heat exchanger and out at 100'C. Determine the amount (kg/s) of water coming in at 100 kPa, 20°C that the air can heat to the boiling point and the heat transfer rate (in kW) from...
7. Steam leaves an industrial boiler at 827.4kPa and 171.6°C (hf = 727.25 kJ/kg, hfg = 2043.2 kJ/kg ). A portion of the steam is passed through a throttling calorimeter and is exhausted to the atmosphere when the calorimeter pressure is 101.4 kPa and a temperature of 115.6°C (h= 2707.6 kJ/kg ). How much moisture does the steam leaving the boiler contain ? 8. During the polytropic process of an ideal gas, the state changes from 138 kPa and 5°C...
Problem 4 – Entropy transfer in a control volume (18 pts) An adiabatic reversible steam turbine steadily processes 2 kg/s of steam at 5 MPa and 450°C, which is exhausted at 100 kPa and 100°C. The turbine exhibits an isentropic efficiency of 0.85. a) Draw a schematic representation of the system with all the energy interactions involved. (2pts) b) Determine the h (kJ/kg) and s (kJ/kg-K) at the inlet. (2 pts) c) Determine the actual h (kJ/kg) and s (kJ/kg-K)...