15.05

Question 1

What is the function of the combustion chamber

Answer 1

To produce a hot stream of gas for turbines and jet nozzle

Question 2

What two main components does a combustion chamber have

Answer 2

Casing and flame tube (inside casing)

Question 3

What does a flame tube do

Answer 3

Controls and guides the flame

Question 4

What two conditions will you need to have a good combustion

Answer 4

Ratio of air:fuel is correct

Air velocity is slow so that that combustion is completed inside the chamber

Question 5

What is the ratio for complete combustion of a kerosene-air mixture

Answer 5

15:1
Air:fuel

Question 6

What are the two types of airflow in combustion

Answer 6

Primary airflow

Secondary airflow

Question 7

Where is the primary airflow used and what percentage of the airflow comes from the compressor

Answer 7

For the combustion process and approximately 20-30%

Question 8

What temperature do we get at the centre of the flame

Answer 8

2000 degrees C

Question 9

The secondary air is mainly used for what

Answer 9

Cooling

Question 10

What are the three types of combustion chambers

Answer 10

1. Can-type
2. Can-annular
3. Annular

Question 11

Can-type chambers can have what type of chambers

Answer 11

Single chambers and multi-can chambers

Question 12

What is an advantage of a can-type combustion chamber

Answer 12

Simple design, very good structural strength and can be removed and replaced individually

Question 13

What is the disadvantage of can-type combustion chamber

Answer 13

Heavy and need a lot of space. Also need complex air supply ducts

Question 14

What is the disadvantage of can annular combustion chamber

Answer 14

Aerodynamic losses are quite high and the ignition from one flame tube to the other is difficult

Question 15

What is the most common used combustion chamber

Answer 15

Annular type

Question 16

What are the chamber casing called in maintenance documentation

Answer 16

Diffuser case or the compressor rear frame

Question 17

What are the three major parts in flame tube of annular combustion

Answer 17

The dome
Inner liner
Outer liner

Question 18

What does the combustion case do

Answer 18

Carries the structural load between the compressor case and the turbine case

Question 19

What does a flame tube do

Answer 19

Stablilzes the flame during combustion

Question 20

What are the external components of a combustion chamber

Answer 20

Fuel nozzle and igniter plugs

Question 21

What three things does a combustion case have

Answer 21

Outer wall
Inner wall
Diffuser

Question 22

What else is located on the outer walls of a combustion case

Answer 22

Fuel nozzle pads and igniter bosses

Question 23

What are the main components of the flame tube

Answer 23

Outer inner liner
Outer inner cowl
Dome

Question 24

What does the dome in a flame tube do

Answer 24

Connects the inner liner with the outer liner

Question 25

The primary airflow enters the flame tube through what

Answer 25

Swirl vanes

Question 26

What is the cooling method known as in flame tube cooling

Answer 26

Film cooling

Question 27

What is the more sophisticated method of film cooling

Answer 27

Transpiration cooling requires less air for cooling

Question 28

What are liner segments

Answer 28

Detachable titles

Question 29

What is one method used to protect the ,arterial from heat

Answer 29

Thin coating of ceramic material on the inner surface