How can you tell if a turbofan or turbojet engine is out of trim? There will be a high exhaust gas temperature at the target engine pressure ratio for takeoff power. Name the different types of compressor blade damage that may be found during inspection. Dents, cracks, galling, pitting, scratches, burrs, burns, gouges.
Why is it important that a turbojet engine be allowed to cool before it is shut down after it has been operated at a high power setting?
Why is it important that a turbojet engine be allowed to cool before it is shut down after it has been operated at a high power setting? If the engine is shut down while it is hot, there is a possibility that the shroud will contract around the turbine wheel and seize the rotor.
What determines the amount of air passing through the turbine engine?
What determines the amount of air passing through a turbine engine? Compressor speed, forward speed of the aircraft, and air density.
What is the function of the accessory section used on a turbine engine?
The accessory section of the gas turbine engine has various functions. The primary function is to provide space for the mounting of accessories necessary for operation and control of the engine. Generally, it also includes accessories concerned with the aircraft, such as electric generators and hydraulic pumps.
What is difference relationship between the jet engine and the turbine engine?
A jet engine is designed to use only its exhaust as its main thrust force. A turbine engine usually gathers its jet exhaust to spin a geared turbine assembly attached to a gearbox (and thence to a propeller, for example). So the propeller is the main source of thrust. In effect, a jet engine is also a turbine.
How are engines usually shut down?
On turbine engines that have a thrust reverser, retarding the aircraft throttle to idle or power lever to OFF cuts the fuel supply to the engine and shuts down the engine. On engines equipped with thrust reversers, this is accomplished by means of a separate fuel shutoff lever or switch.
At what altitude do jet engines stop working?
Flying at a typical altitude of 36,000 feet (about seven miles), an aircraft that loses both engines will be able to travel for another 70 miles before reaching the ground.
Where is the highest pressure in a turbine engine?
Pressure is highest either at the end of the compressor, or right before the power turbine section. Temperature is going to be the highest in the combustion section.
What type of oil system is usually found on turbine engines?
(1) Wet sump oil systems are most commonly used in gas turbine engines.
Why does the pressure drop slightly or remain constant in the combustion section of a turbine engine?
The air moves¹ in direction of decreasing pressure except where forced by the compressor. So the pressure must be decreasing to maintain desired flow. If the pressure was increasing, the flow would stop and reverse and the engine would stop operating. … If the pressure was constant, it would keep moving.
Which is the only component that will drive the gear box?
2 Answers. The accessory gearbox is generally driven by the N2 shaft (connecting the high-pressure turbine to the high-pressure compressor) and in turn drives the engine accessories such as generators, hydraulic pumps, oil pumps, etc.
How are multiple features like fuel nozzles & flange bolts that go around the circumference of a turbine engine numbered?
How are multiple features (like fuel nozzles & flange bolts) that go around the circumference of a turbine engine numbered? The circumference of a turbine engine are numbered clockwise from the rear number 1 at the top or 12’0 clock position.
What are the two basic elements of the accessory section?
The basic elements of the accessory section are:
- The accessory case, which has machined mounting pads for the engine-driven accessories, and.
- The gear train, which is housed within the accessory case.
How does a turbofan engine start?
So to start a turbofan engine, you need to spin the compressor fast enough to start pushing compressed air into the diffuser and combustion chamber. … During a start sequence, the engine core needs to spin at 14% of its maximum speed before the igniters start.
Why are jet engines so expensive?
Jet engines are so expensive, because they are getting more and more sophisticated and fuel efficient. After landing the A380, the controls to shutdown the engine were not working. … Jet engines are so expensive, because they are getting more and more sophisticated and fuel efficient.
Why is a turbofan better than a turbojet?
Low-bypass-ratio turbofans are more fuel efficient than the basic turbojet. A turbofan generates more thrust for nearly an equal amount of fuel used by the core because the fuel flow rate is changed by slightly when adding the fan. As a result, the turbofan offers high fuel efficiency.