This document discusses cold flow analysis of a gas turbine combustor using computational fluid dynamics (CFD). CFD is used to model airflow and fuel injection without reactions to capture mixture formation. The CFD model accounts for moving geometry interactions with fluid dynamics. Cold flow simulations provide useful information on turbulence and mixing to ensure proper combustion conditions. The document outlines objectives of combustor design like satisfactory mixing and stable flow patterns with minimal losses. Numerical analysis and governing equations are presented along with experimental data and graphs showing variation in properties like temperature, pressure, and pattern factor.

1. COLD FLOW ANALYSIS OF GAS
TURBINE COMBUSTOR
PRESENTED BY
ANIKET KUMAR
CHAURASIYA
2015FE07
GUIDANCE OF:DR.BIRESHWAR
PAUL
MOTILAL NEHRU NATIONAL INSTITUTE OF
TECHNOLOGY

2. Cold flow analysis
 Cold flow analysis involves modeling the airflow and
possibly the fuel injection in the transient engine cycle
without reactions.
 The goal is to capture the mixture formation process by
accurately accounting for the interaction of moving geometry
with the fluid dynamics of the Induction process.
 Setting up the CFD model for cold flow analysis involves
additional work in specifying the necessary information to
compute the motion of the fluid particle in addition to the
boundary conditions, turbulence models and other
parameters.

3. Contd…
 The changing characteristics of the air flow jet that
tumbles into the chamber with swirl via injector and
the exhaust jet, along with the turbulence production
from swirl and tumble due to compression and squish.
 This information is very useful to ensure that
conditions in the combustion chamber at the end of the
compression stroke are right for combustion and flame
propagation

4.  High turbulence levels facilitate rapid flame
propagation and complete combustion during process .
A well mixed and highly turbulent air flow is critical to
ensure the right air/fuel ratio throughout the
combustion.
 cold flow simulations do not include the significant
thermodynamic changes that accompany combustion,
the flow

5. GAS TURBINE COMBUSTOR
 A combustor is a component or area of a gas
turbine, where combustion takes place. In a gas
turbine engine, the combustion chamber is fed high
pressure air by the compression system. The
combustor then heats this air at constant pressure

8. CFD ANALYSYS
• Computational fluid dynamics, usually abbreviated
as CFD, is a branch of fluid mechanics that uses numerical
analysis and algorithms to solve and analyze problems that
involve fluid flows
• Computers are used to perform the calculations required to
simulate the interaction of liquids and gases with surfaces
defined by boundary conditions

9. Contd…
• non-reacting flow analysis of a gas turbine combustion
system. The method is based on the solution of Navier-
Strokes equations using generalised non-orthogonal
coordinate system.
 The combustion system includes swirler vane passages,
fuel nozzles, rotor bleed, customer bleed, air-blast atomiser,
swirl cone, and all holes in primary , dilution , dome, flare.
 These models are used to optimise the design of the
combustor and its subcomponents, and reduce cost, time,
and the number of experiment.

10. Numerical analysis
 A numerical study was performed for obtaining
the flow field characteristics of annular gas turbine
Combustor. It involves solving the following
equations:
(a) Continuity equation
(b) Momentum equation
(c) Energy equation
(d) Turbulence-modelling equations

11. Governing equation
Continuity equation
Momentum equation
Energy equation

12. Objective
 In the diffuser and the annulus, the main objectives are to
reduce the flow velocity and to distribute the air in the
prescribed quantities to all the combustor zones, while
maintaining uniform flow condition with no parasitic losses or
flow recirculation of any kind.
 primary objective of combustor design is to achiev satisfactory
mixing within the liner and a stable flow pattern throughout the
entire combustor, with no parasitic losses and minimum length
of prediffuser and total-pressure loss

13. Experimental data

14. Variation in different property
Based on above experimental these graph drawn

15. Pattern factor
 The exit temp profile directly decides the life of the turbine
blade and hence the overall engine life, thus it’s an
important parameter to be studied
 Pattern factor highlights the overall temperature
distribution factor.

16. Temperature variation

17. Contd…
Variation in pressure and temperature