The Rolls-Royce Trent Engine
Michael Cervenka
Technical Assistant to Director - Engineering & Technology
5 October 2000
Rolls-Royce Today
 World No 2 in aero-engines
 World leader in marine propulsion systems
 Developing energy business
 Annual sales of over £4.5 billion
 Orders of over £13 billion
Newton’s 3rd Law
MV
Equilibrium
Reaction
Thrust = Mass x Velocity (MV)
Action
Propeller versus Jet Propulsion
Mvjet
Propeller - moves
LARGE MASS of
air at low velocity
Mvaircraft
Thrust = M(vaircraft - vjet)
Thrust = m(Vaircraft - Vjet)
mVjet
mVaircraft
Jet - moves small
mass of gas at HIGH
VELOCITY
Jet Engine Layout
Compressor
Combustion
Chamber
Exhaust
Nozzle
mVaircraft
mVjet
Shaft
Turbine
Different Jet Engine Types
Civil turbofan Trent
Military turbofan EJ200
Different Jet Engine Types - Mechanical drive
Turboprop - AE 2100
Turboshaft - RTM322
Marine Trent
Industrial Trent
Piston Engine versus Turboprop
Air intake
Exhaust
Piston engine
Intermittent
Compression
Air intake
Jet engine
driven propeller
(Turboprop)
Combustion
Continuous
Exhaust
Pressure and Temperature
40
Pressure
(atmospheres)
0
1500
Temperature
(degrees C)
0
Axial Compressor and Turbine Operation
Axial Compressor and Turbine Operation
Compressor Stages
Turbine Stages
Rotating
Rotor Row
Rotating
Rotor Row
Rotating
Rotor Row
Rotating
Rotor Row
Gas flow
Airflow
Stationary
Vane Row
Stationary
Vane Row
Stationary
Nozzle Row
Stationary
Nozzle Row
Multiple Shafts - Trent 95,000 lbs Thrust
LP System
1 Fan stage
IP System
8 Compressor stages 5 Turbine stages
>3,000 rpm
1 Turbine stage
>7,500 rpm
HP System
6 Compressor stages
1 Turbine stage
>10,000 rpm
Combustor Operation
Combustor Operation
Primary zone
Dilution zone
Intermediate
zone
Fuel spray
nozzle
Reverse Thrust
Net 25% to 30% thrust
85% thrust
15% thrust
New Product Introduction Process
Stage 1:
Preliminary concept defined for planning purposes
Preliminary
Concept
Product definition stages
Definition Stage 2:
Full
Concept
Definition
Full concept defined, product launched
Stage 3:
Product
Realisation
Product developed, verified and approved
Stage 4:
Production
Capability
Acquisition
Product produced and
delivered to customer
Stage 5:
Customer
Support
Product used by customer
New Project Planning Process
BUSINESS MODEL
MARKETING MODEL
Market Size
Selling Price
Concessions
Operating Costs
Payload Range
Maintenance Costs
Fuel Burn
Commonality
Units sold
Unit Cost
Selling Price
Concessions
Sales Costs
Development Costs
Guarantee Payments
Spares Turn
Spares Price
ENGINEERING MODEL
Safety
Unit Cost
Weight
Noise
Emissions
Geometry
Reliability
Operability
Performance
102 Million Hours of Service
Million hours
100
90
80
70
60
RB211 & Trent operating hours
August 2000
-22B
-524
-535
Trent
26.7 million hours
48.5 million hours
25.4 million hours
2.2 million hours
4260
3592
103
engines ordered
engines delivered
customers currently flying
with RB211 or Trent engines
Trent 800
Trent 700
50
-535C
-524D -535E4
40
30
20
10
-524
-22
-524H
-524G
0
1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000
Entry into service
Why 3 Shafts?
Long / Medium-Haul
Short / Medium-Haul
(40,000-100,000lbs thrust):
(8,000 - 40,000lbs thrust):
Range
Fuel consumption
Acquisition Cost
Maintenance
• Requires high:
- Overall pressure ratio
- Turbine entry temperature
- Bypass ratio
Three-Shaft Configuration
• Simpler engine, hence moderate:
- Overall pressure ratio
- Turbine entry temperature
- Bypass ratio
Two-Shaft Configuration
Evolution of Trent Family
Fan diameter - in.
Trent 800
Trent 8104
Trent 900
Boeing 777
110
95,000lb Scaled 104,000lb Scaled 80,000lb
core
core
Trent 700
Trent 500
Trent 600
Airbus A3XX
Airbus A330
97.5
72,000lb
56,000lb
65,000lb
Boeing 747
RB211-524G/H-T
Airbus A340
86.3
60,000lb
Boeing 767
Trent 700 & 800
Phase 5 low
emissions
combustor
Single crystal HPT
Single Crystal
Uncooled
IP turbine blade
Fan diameter
increased to
2.8m
(110.3in.)
Trent 800
Fan diameter
2.47m
(97.4in.)
Four-stage
LP turbine
Five-stage
LP turbine
Area of significant commonality
Area of main geometric change
8 Stage IPC
3 Variables
Trent 700
Trent 500
Scaled IP & HP
Scaled combustor
compressor
with tiled cooling
3D Aerodynamics
Trent
500
Trent
700
HP & IP turbines have
increased blade speeds
High lift LP turbine blading
Material Strength
Specific Strength
Titanium Alloy
Nickel Alloy
Steel
Aluminium Alloy
Temperature
Engine Materials
Titanium
Nickel
Steel
Aluminium
Composites
Fan Blade Technology
Clappered
+ 4% efficiency
Wide-chord fan
Wide-chord Fan Technology
1st generation:
1984
Honeycomb
construction
2nd generation:
1995
DB/SPF
construction
Fan Section
Swept Fans
Compressor Aerodynamics
Trent 500 Tiled Combustor
Cold supporting wall
Tiles reduce wall cooling air
requirements making more
air available for NOx
reduction
A significant cost reduction
relative to conventional
machined combustors is
also achieved
Cast tile
Thermal barrier coating
Large primary zone
volume for altitude
re-light
Large airspray injectors
for improved mixing
and smoke control
Small total
volume for
NOx control
Improvements in Materials
Equiaxed
Directionally
Single Crystal
Crystal Structure Solidified Structure
Turbine Cooling
Single pass
Cooling air
Multi-pass
Thermal Barrier
Coating
Performance Trends
Straight Low Medium High
bypass bypass bypass
jet
50
40
%sfc
improvement
(bare engine)
30
Propulsive
efficiency
Cycle efficiency
20
Thermal
efficiency
10
Datum
Avon Conway Spey
1958 1960
1963
Component
efficiency
-22B -524B4/D4-535E4 -524G/H 700
1973 1981
1983 1988
1994
RB211
800
1995
Trent
500
2000
Electric Engine Concepts
New Engine Architecture
with reduced parts count,
weight, advanced cooling,
aerodynamics and lifing
Air for pressurisation/cabin
conditioning supplied by
dedicated system
Pylon/aircraft mounted engine
systems controller connected
to engine via digital highway
All engine
accessories
electrically
driven
Internal active magnetic bearings and
motor/generators replace conventional
bearings, oil system and gearboxes
(typical all shafts)
Generator on fan shaft
provides power to airframe
under both normal and
emergency conditions
Compressor Weight Reduction
Conventional
disk & blades
Blisk - up to 30%
weight saving
Bling - Ti MMC
- up to 70%
weight saving
Metal Matrix Composites
Specific Strength
Titanium Metal Matrix Composite
Titanium Alloy
Nickel Superalloy
Temperature (degrees C)
Future Emissions Improvements
Main
Pilot
Double-annular combustor
Main
Pilot
Pre-mixed double-annular combustor
Future Aircraft Configurations
Large diameter
duct
Contra-rotating
fan
Gas generator
Contra-rotating
turbine
Flying wing
Blended wing aircraft may offer
up to 30% reduction in fuel
consumption - 40% if combined
with electric engine concepts
Conclusion
 The three-shaft concept is now recognised as a
world leader
 Customer-focused competitive technology is
critical to its success
 Success is a tribute to many generations of people
 The RB211 & Trent family has a long and secure
future
Rolls-Royce