BMCT 2123 THERMODYNAMICS I TUTORIAL 04 1 FACULTY OF MECHANICAL ENGINEERING BMCT 2123 THERMODYNAMICS I TUTORIAL 04 1. Air enters an adiabatic nozzle steadily at 300 kPa, 200 o C, and 30 m/s and leaves at 100 kPa and 180 m/s. The inlet area of the nozzle is 80 cm 2 . Determine: a) the mass flow rate through the nozzle b) the exit temperature of the air c) the exit area of the nozzle. 2. Steam at 5 MPa and 500 o C enters a nozzle steadily with a velocity of 80 m/s, and it leaves at 2 MPa and 400 o C. The inlet area of the nozzle is 50 cm 2 , and heat is being lost at a rate of 90 kJ/s. Determine: a) the mass flow rate of the steam b) the exit velocity of the steam c) the exit area of the nozzle. 3. Nitrogen gas at 60 kPa and 7 o C enters an adiabatic diffuser steadily with a velocity of 200 m/s and leaves at 86 kPa and 22 o C. Determine: a) the exit velocity of the nitrogen b) the ratio of the inlet to exit area, A 1 /A 2 . 4. Steam flows steadily through an adiabatic turbine. The inlet conditions of the stem are 10 MPa, 450 o C, and 80 m/s, and the exit conditions are 10 kPa, 92 percent quality, and 50 m/s. The mass flow rate of the steam is 12 kg/s. Determine: a) the change in kinetic energy b) the power output c) the turbine inlet area. 5. Air flows steadily through an adiabatic turbine, entering at 1 MPa, 500 o C, and 120 m/s and leaving at 150 kPa, 150 o C, and 250 m/s. The inlet area of the turbine is 80 cm 2 . Determine: a) the mass flow rate of the air b) the power output of the turbine. 6. Air is compressed from 100 kPa and 22 o C to a pressure of 1 MPa while being cooled at a rate of 16 kJ/kg by circulating water through the compressor casing. The volume flow rate of the air at the inlet conditions is 150 m 3 /min, and the power input to the compressor is 500 kW. Determine: a) the mass flow rate of the air b) the temperature at the compressor exit. UNIVERSITI TEKNIKAL MALAYSIA MELAKA KARUNG BERKUNCI 1200 AYER KEROH 75450 MELAKA

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BMCT 2123 THERMODYNAMICS ITUTORIAL 04

FACULTY OF MECHANICAL ENGINEERINGBMCT 2123 THERMODYNAMICS I

TUTORIAL 04

1. Air enters an adiabatic nozzle steadily at 300 kPa, 200oC, and 30 m/s and leaves at100 kPa and 180 m/s. The inlet area of the nozzle is 80 cm2. Determine:

a) the mass flow rate through the nozzleb) the exit temperature of the airc) the exit area of the nozzle.

2. Steam at 5 MPa and 500oC enters a nozzle steadily with a velocity of 80 m/s, and it leavesat 2 MPa and 400oC. The inlet area of the nozzle is 50 cm2, and heat is being lost at a rateof 90 kJ/s. Determine:

a) the mass flow rate of the steamb) the exit velocity of the steamc) the exit area of the nozzle.

3. Nitrogen gas at 60 kPa and 7oC enters an adiabatic diffuser steadily with a velocity of200 m/s and leaves at 86 kPa and 22oC. Determine:

a) the exit velocity of the nitrogenb) the ratio of the inlet to exit area, A1 / A2.

4. Steam flows steadily through an adiabatic turbine. The inlet conditions of the stem are10 MPa, 450oC, and 80 m/s, and the exit conditions are 10 kPa, 92 percent quality, and50 m/s. The mass flow rate of the steam is 12 kg/s. Determine:

a) the change in kinetic energyb) the power outputc) the turbine inlet area.

5. Air flows steadily through an adiabatic turbine, entering at 1 MPa, 500oC, and 120 m/s andleaving at 150 kPa, 150oC, and 250 m/s. The inlet area of the turbine is 80 cm2.Determine:

a) the mass flow rate of the airb) the power output of the turbine.

6. Air is compressed from 100 kPa and 22oC to a pressure of 1 MPa while being cooled at arate of 16 kJ/kg by circulating water through the compressor casing. The volume flow rateof the air at the inlet conditions is 150 m3/min, and the power input to the compressor is500 kW. Determine:

a) the mass flow rate of the airb) the temperature at the compressor exit.

UNIVERSITI TEKNIKAL MALAYSIA MELAKAKARUNG BERKUNCI 1200

AYER KEROH75450 MELAKA

BMCT 2123 THERMODYNAMICS ITUTORIAL 04

7. Helium is to be compressed from 120 kPa and 310 K to 700 kPa and 430 K. A heat loss of20 kJ/kg occurs during the compression process. Neglecting kinetic energy changes,determine the power input required for a mass flow rate of 90 kg/min.

8. Refrigerant-134a at 800 kPa and 25oC is throttled to a temperature of –20oC. Determine:a) the pressure at the final stateb) the internal energy at the final state.

9. Air at 2 MPa and 30oC is throttled to the atmospheric pressure of 100 kPa. Determine thefinal temperature of air.

10. A hot-water stream at 80oC enters a mixing chamber with a mass flow rate of 0.5 kg/swhere it is mixed with a stream of cold water at 20oC. If it is desired that the mixture leavethe chamber at 42oC, determine the mass flow rate of the cold-water stream. Assume allthe streams are at a pressure of 250 kPa.