Question

A turbojet aircraft is flying with a velocity of 320 m/s at a certain altitude, where the ambient conditions are 32 kPa and -32°C. The pressure ratio across the compressor is 12, and the temperature at the turbine inlet is 1400K. Air enters the compressor at a rate of 40 kg/s, and the and the jet fuel has a heating value of 42700 kJ/kg. Assuming ideal operations for all components and constant specific heats for air at room temperature, (Cp=1.005 kJ/kg°K, and k=1.4) determine:

a) the velocity of the exhaust gases.

b) the propulsive power developed.

Answer #1

As a propulsion engineer, you are tasked with testing
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air-standard basis based on the Brayton cycle. Air, with a velocity
of 265 m/s and volumetric flow rate of 230 m3/s, enters
the diffuser at 18 kPa, -57oC, and exits at 30
kPa. The compressor pressure ratio is 15 to 1. The
maximum temperature exiting the combustor is 1087oC. The
pressure exiting the nozzle is...

A turbojet aircraft flies at 575 mph at an altitude of 16,500
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Air is heated by exhaust gases that flow in a heat exchanger, as
shown in the figure. The
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Exhaust gases inlet state is 527°C, 822 kJ/kg, 64 m/s while the
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and the exit temperature of air. [Cp-air = 1.005 kJ/kg...

1) A nozzle is a device for increasing the velocity of a
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An airplane is flying at an altitude of 10 km at 120 m/s. Its
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I ONLY NEED ANSWERS TO F.) AND G.)
I SOLVED THE REST. THANK YOU!
The Boeing 747 has a cruising altitude of 45,000 feet and
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