about gas turbine

2. INTRODUCTION:
• A gas turbine is a machine delivering mechanical power . It
does this using a gaseous working fluid. Hot gases are
expands in turbine, which spin the turbine wheels.

3. SIMPLE GAS TURBINE

4. Working principle :
Air is compressed(squeezed) to high pressure by a
compressor.
Then fuel and compressed air are mixed in a combustion
chamber and ignited.
Hot gases are given off, which spin the turbine wheels.
Gas turbines burn fuels such as oil, natural gas and
pulverized(powdered) coal.
Gas turbines have three main parts:
i) Air compressor
ii) Combustion chamber
iii) Turbine

5. 1-inlet fluid
2-compressed fluid
3-fuel/ignited
4-tranfer of K.E of heat in to mechanical energy
5-exaust

6. ENERGY FLOW DIAGRAM

7. WORKING CYCLE:
• The Brayton cycle is a thermodynamic cycle that describes
the workings of the gas turbine engine.
• THE T-S DIAGRAM SHOWS:
• 1-2 Isentropic compression;(No change in entropy)
• 2-3 Constant-pressure heat addition;
• 3-4 Isentropic expansion;
• 4-1 Constant-pressure heat rejection

8. A. Low pressure spool
B. High pressure spool
C. Stationary components
1. Nacelle
2. Fan
3. Low pressure compressor
4. High pressure compressor
5. Combustion chamber
6. High pressure turbine
7. Low pressure turbine
8. Core nozzle
9. Fan nozzle

9. TYPE OF TURBINE
IMPULSE TURBINE:
A turbine in which the expansion of the fluid, is completed in a
static nozzle, the torque being produced by the change in
momentum of the fluid impinging on curved rotor blades
REACTION TURBINE:
A reaction turbine doesn't change the direction of the fluid flow
as drastically as an impulse turbine: it simply spins as the
fluid pushes through and past its blades. Wind turbines are
perhaps the most familiar examples of reaction turbines.

11. BLADES OF GAS TURBINE:
• A turbine blade are responsible for extracting energy from
the high temperature, high pressure gas produced by
the combustor.
• Turbine blades face high temperatures, high stresses, and a
potential environment of high vibration.
• All three of these factors can lead to blade failures, potentially
destroying the engine, therefore turbine blades are carefully
designed to resist these conditions.
• Ceramic matrix composites(CMC) are being developed for
use in turbine blades.
• The main advantage of CMC materials over conventional
super alloys is their light weight and high temperature
capability

13. CAPACITY OF GAS TURBINE