Turbine Engines Oral

Front 1

What are the major components of a typical gas turbine engine?

Back 1

A typical gas turbine engine consists of an air inlet, a compression section, a combination section, a turbine section, an exhaust section, and the accessory section.

Front 2

What are the two principal types of compressors used in turbojet aircraft?

Back 2

The two most common compressors in use today are the centrifugal flow and the axial flow types

Front 3

What are the three types of combustion chamber systems?

Back 3

They are the can type, they can-annular type, and the annular type.

Front 4

What is the purpose of the interconnector tubes between can-type combustion chambers?

Back 4

To spread the flame to the combustion chambers that are not equipped with igniter plugs during engine starting

Front 5

What prevents burning of the liner walls in Can-type combustion chambers?

Back 5

Louvers are provided along the axial length of the liners to direct a cooling layer of air along the inside wall of the liner.

Front 6

What types of damage may be found when inspecting compressor blades?

Back 6

Dents, scratches, gouges, galling, burns, burrs, pitting, and cracks

Front 7

What is the location and function of the diffuser section in a turbine engine?

Back 7

The diffuser is the divergent section of the engine located between the compressor section and the burner cans. its function is to change the high-velocity compressor discharge air to static pressure.

Front 8

Where are stressed rupture cracks most likely to occur on turbine blades?

Back 8

They usually appear as small hairline cracks on or across the leading or trailing edge of the blades. The cracks appear at right angles to the edge length.

Front 9

How are compressor blades attached to a disk-type rotor?

Back 9

The compressor blades are fitted into the disks by either Bulb-type or fir tree-type roots. The blades are then locked by means of screws, peening, locking wires, pins, or keys.

Front 10

What is the purpose of nozzle diaphragm or turbine nozzle?

Back 10

The turbine nozzle prepares the combustion mass airflow to drive the turbine rotor. First, they change a portion of the heat and pressure energy to velocity energy. The fixed vanes are shaped and set at such an angle that they form a number of small nozzles that discharge the gases at extremely high speeds. The second purpose of the turbine nozzle is to deflect the gases so they strike the turbine at the most efficient angle for maximum turbine rotation

Front 11

What is the major difference between a turboprop and a turbojet engine?

Back 11

A turboprop engine usually has more turbine stages than the turbojet engine. In addition to operating the compressor and accessories, the turboprop turbine must also drive a propeller.

Front 12

What is a turbo fan engine?

Back 12

A Turbofan engine is, in principle, the same as a turboprop except that the propeller is replaced by a duck-enclosed axail flow fan.

Front 13

What is the effect of air density on the thrust of a turbine engine?

Back 13

Air density determines the mass of air that is used by a jet engine? the factors that affect density are the temperature and pressure of the air. If density increases, thrust increases, and vice versa. An increase in air temperature entering an engine will cause a decrease in density and thrust. An increase in air pressure entering the engine will cause an increase in density and thrust. With a given throttle setting, engine thrust will vary if the temperature or pressure of the air entering the engine changes.

Front 14

What are the two most common types of thrust reverse?

Back 14

The mechanical blockage tape and the arrow dynamic blockage type

Front 15

What is a split compressor system in a turbine engine?

Back 15

The split compressor system requires two concentric shafts joining the turbine stages to their receptive compressors.

Front 16

What is one method of relieving thermal stress on a turbine disc?

Back 16

One means is to bleed cooling air back onto the face of the disk

Front 17

What may be the indication if a turbojet engine is out of trim?

Back 17

The engine has high exhaust gas temperature (EGT) at target engine pressure ratio (EPR) for takeoff.

Front 18

What is a free turbine?

Back 18

The turbine wheel that, rather than driving the compressor rotor, drives a propeller or helicopter transmission

Front 19

Explain the main difference and advantage of turbofan over turbojet engines.

Back 19

A turbo fan engine uses a fan to bypass some air around the engine core and to provide thrust. The Vantage is that this provides additional thrust without increasing fuel flow.

Front 20

Name the major components in a gas turbine engine.

Back 20

Air inlet, compressor section, combustion section, turbine section, exhaust section, gearbox and accessory section.

Front 21

What determines the amount of airflow through a turbine engine?

Back 21

The forwards be of the aircraft, compressor Speed, and air density.

Front 22

Name the two types of compressors commonly use in turbine engines.

Back 22

Axle and center fugal flow compressors

Front 23

Name two different methods for a thatching turbine engine rotor blades to the rotor disks.

Back 23

Drovetail-type root

Bulb-type root

Fir tree-type root

Front 24

What is a split compressor system?

Back 24

Also call dual or twin spool compressors, these are connected to the turbine section with two rotor shifts, one inside the other.

Front 25

What are the different types of combustion chambers use and turbine engines?

Back 25

Can, annular, Can-annular, and reverse flow annular.

Front 26

What prevents the combustion chambers from burning?

Back 26

Cooling air along the inside of the liner.

Front 27

What is the purpose of the interconnecting tubes attached between Can-type combustion chambers?

Back 27

For flame propagation during the start.

Front 28

What is the purpose of the interconnecting tubes attached between Can-type combustion chambers?

Back 28

For flame propagation during the start.

Front 29

What functions do axial flow turbine nozzles perform?

Back 29

They direct the mass airflow to drive the turbine rotor at a specific angle.

Front 30

How is thermal stress relieved on a turbine desk?

Back 30

By directing bleed air onto the face of the disk, or by grooves being cut in the disk.

Front 31

What are carbon seals use for in turbine engines question

Back 31

They are used as oil seals for the rotor shaft bearings.

Front 32

What are the problems caused for a turbojet or Turbofan engines having high exhaust gas temperatures, low RPM, and high fuel flow at all engine pressure ratios?

Back 32

Turbine damage or loss of turbine efficiency due to wear.

Front 33

Why are compressor washers perform and what methods are commonly used?

Back 33

To remove any contaminants from the compressor section and improve engine performance. The fluid wash and abrasive great washer, used.

Front 34

How can you tell if a turbofan Engine is out of trim?

Back 34

It would be a high exhaust gas temperature at the target engine pressure ratio for takeoff power.

Front 35

Name the different types of compressor blade damage that may be found during inspection.

Back 35

Dents, cracks, Galang, pitching, scratches, birds, burns, gouges

Front 36

What kind of markers can be used to mark the parts in hot and cold sections doing repairs?

Back 36

Layout dye, felt tip marker, chalk.

Front 37

How does relative humidity affect turbine engine?

Back 37

Negligible effect