Intercontinental passenger super power: GENX turbofan engine
February 28, 2011 0 CommentsIntercontinental passenger super power: GENX turbofan
engine
Recently, the Boeing 747-8 Intercontinental's latest
successful aircraft off the assembly line. The new aircraft, Boeing 747-8 Intercontinental Boeing 787
using only a number of breakthrough technologies, the most notable
is the adoption of GE's new generation of commercial high bypass
ratio turbofan engine - GENX. Then this type of engine
performance? What it uses advanced technology? Netease military below for resolution.
Line-off ceremony on the Boeing 747-8 Intercontinental
latest aircraft, equipped with four GENX its high bypass ratio
turbofan engine.
Boeing's newest intercontinental aircraft off the assembly
line 747-8
February 14, 2011 3:00 Beijing time, the U.S. aircraft
maker Boeing famous in its day in the Everett plant in Washington
state held a Boeing 747-8 intercontinental aircraft
ceremony. Approximately 10,000 guests attended to celebrate,
including customers, Boeing employees, government officials,
partners and suppliers. They gathered at the Everett factory to witness the theme
of "love and then the world's leading future," the 747-8
Intercontinental aircraft ceremony.
The Boeing 747-8 is the competition of Airbus A380
aircraft, its fuselage length of 76.3 meters, more than 5.6 meters
long fuselage 747-400. Longer part of the seating capacity of 51, which makes the
aircraft in a typical three-class configuration carrying 467
passengers. Compared with all other large aircraft, this large
capacity of the new aircraft provides airlines the lowest operating
costs, the best economy, and better environmental
performance.
It is also the Boeing 400-500 aircraft on the market-level
models only. The new Boeing 747-8 intercontinental aircraft in addition
to using the Boeing 787 "Dream" a number of breakthrough
technologies flight, the most notable is that it uses a new
generation of GE's commercial high bypass ratio
vortex fan engine - GENX.
Is by far the largest thrust GE90 engine, and follow-up
it's GENX engine is derived from a series of U.S. civilian bypass
ratio turbofan engine technology crystallization of pre-research
project.
GE90: the world's largest aircraft engine
thrust
GE90 engine is a subsidiary of General Electric Company,
GEAE "General Electric Aircraft Engine Company" developed
commercial high-bypass ratio turbofan engine thrust
large. GE90-115B engine is the model recorded in the Guinness
Book of World Records the world's largest aircraft engine thrust,
ground bench had reached over 56.9 tons in the maximum
thrust. GE90 officially in November 1995 put the commercial
market, Boeing 777 series aircraft currently used.
GE90 advanced design a good foundation for the
GENX
GE90 engines and follow-up of the GENX engine is derived
from a series of U.S. civilian bypass ratio turbofan engine
technology crystallization of pre-research
project. GE90 using large-diameter single-stage breakthrough in
wide-chord composite fan blades, not high bypass ratio turbofan
engine used in the traditional titanium fan blades, thus greatly
reducing the weight of the fan assembly. The low tip speed fan, elastic deformation to absorb
impact energy and re-distribution, blade root slot in the tongue
and cushion the impact of deflection means and the local parcel
titanium fan blades ensure the success of the anti external
material to combat performance; by coatingPolyurethane corrosion-resistant coating and the use of
special silk sutures and other parts of composite delamination ways
to enhance the fan blade corrosion resistance.
GE90 of ten with 23 high pressure compressor pressure
ratio, structural strength and aerodynamic loads and the GE design
developed in cooperation with the French company CFM56 engines
similar. Since the thrust GE90 very demanding, and thus selected
for the core flow and the size of a large machine, the machine
high-pressure compressor blade length was significantly greater
than other high bypass ratio turbofan
engine. GE90 GE's unique use of low-pollution combustion chamber
design and double loop applied on the previously used in turbine
blade film cooling means. This design effectively reduces NOx emissions and improves
engine performance and durability. GE90 two-stage high pressure turbine, and up to six
low-pressure turbine, and therefore longer life low heat
load.
In general, GE90 composite materials using an epoch-making
fan blades, mature core machine programs, environmental protection,
long life and the most powerful chamber thermodynamic properties,
which for the future development of the GENX laid a very good
technology base.
Boeing 777-200ER aircraft with the GE90-94B engine is a
technological leap second results. The engine in the high-pressure compressor blade using
three-dimensional flow on the overall design.
GENX is a GE company for the Boeing 787 "Dreamliner"
aircraft developed a high bypass ratio (10.0), high total pressure
ratio (45.0), low fuel consumption, low pollution and low noise, a
new generation of engines. In order to meet the 21st century "green aviation"
requirements, GENX not only inherit and develop the past, GE GE90
engine mature engine design, especially technology, to absorb the
GE90 engine development and use of experiences and lessons, but
also uses some of the latest developments advanced technology, therefore, not only to achieve a
higher level of performance, and shorter development
cycle. From the GE90 to GENX, experienced four technical leap
forward.
The first leap forward: The classification of double-loop
radial combustion chamber
November 1995 and put into use on the Boeing 777-200
aircraft used GE90-76B/85B engine. The engine, apart from the most basic characteristics of
GE90 composite fan blades and high-pressure compressor pressure
ratio of 23, but also specifically developed by the GE, the first
generation of double-loop radial graded combustion
chamber. Rating Radial bicyclic successful application of the
combustion chamber in 1995 in the CFM56-5B, CFM56-5B / P and
CFM56-7B engines, the NOx emissions under International Civil
Aviation Organization standard value by 50%.
The second leap: compressor blade design using
three-dimensional flow
November 2000 Boeing 777-200ER aircraft with the GE90-94B
engine GE90-76B/85B engine a step further: a comprehensive
high-pressure compressor blade design using three-dimensional flow;
using the second generation of double-loop classification of the
combustion chamber radial ; reduce the low pressure turbine tip clearance and
improve the efficiency of low-pressure turbine; the fan exit guide
vane at the enhanced seal.
GE90-115B engine is the outcome of the third technical
leap forward, it will reduce the high pressure compressor to
nine.
The third leap: reduced to nine high-pressure
compressor
March 2004 and put into use Boeing 777-200LR and 300ER
aircraft with the GE90-115B engines for the third time skills
upgrading: The higher the compression ratio swept fan blades; the
original high-pressure compressor was reduced to
ten nine; high-pressure turbine blade design also used a
three-dimensional flow; low-pressure turbine blade consistency with
a small leaf; engine control system uses a third-generation
full-authority digital engine control system.
Fourth leap: to further reduce pollution
emissions
2007 put the A380-800 aircraft used by the GP7000 engine
is the GE90 series engine of the latest technological achievements,
the engine is based on the GE90-115B engines to further reduce
pollution emissions and noise reduction technology is
applied. Until 2007, the GP7000 engine, GENX engine based on
technology it needed to complete the basic
accumulation.
Commercial aircraft engine more frequent application of
new technologies
Readers must have the model may have been numerous and
complex technical sort of a bit dizzy head, this is because the
engine on constantly improving the application of new technology
and accumulated experience is the only way for the commercial
success of the engine. Because the opportunities fleeting, commercial engines did
not have time and money for military engine development as more
than a decade, until the engine fully mature before launching a new
generation of models. GE90 engine family after many years of successful
operation, and the accumulation of new technologies, GE has finally
launched a new generation of GENX engine.
As the excellent design to undertake the GE90, GENX engine
thrust is not only big, but fuel consumption, emissions, noise and
direct user charges and so on down to a considerable
level.
As mentioned above, GENX engine is put into use in 1996
GE90 engines (for Boeing 777 aircraft) based on the development,
originally developed for the Boeing 787 aircraft, the Boeing 747-8
and later was chosen as the only power devices.
GENX engine thrust is less than 378 ~ 511 kN GE90,
CF6-80C2 engines is greater than (for the Boeing 747-400 aircraft)
258 kN; use of bypass ratio of up to 10 and total pressure ratio
(45; GE90 engines were 8,40), and high component
efficiency. GE90-76B engine into operation in late 1995, the GENX
engine was successfully developed technology to increase 4 times
after that GENX engine fuel consumption, emissions, noise and so
reduce the cost of direct use to a considerable
level.
GENX engine cruise fuel consumption greatly
reduced
GENX engine for the A330 passenger cruise fuel consumption
than the CF6-80E1A4 engine low 15.4%, than for the B777 aircraft
GE90-94B engines with low 6.9%. GENX engine design for the 333 kN
thrust. In the 1st test, the thrust reached 358 kN, the design is
greater than 7%. Because there are three B787 aircraft to take off the
total mass of different models, so the GENX engine for the B787
aircraft have thrust three different models, namely for the B787-3
of the GENX-1B54 (236 kN) for B787 -8 of the GENX-1B64 (284 kN) for B787-9 in the GENX-1B70
(310 kN); III engine fan diameter are 2.819m.
GENX engine fan blades using GE's 3rd generation composite
materials, which reduce the engine weight. In the compressor at the use of more blisk, which is also
the number of parts, reduced weight.
Fan: Use GE, 3rd generation composite
materials
GENX engine fan blades using GE's 3rd generation composite
materials, shape (swept) Basic with the GE90-115B engine; technical
design of a new generation of three-dimensional flow, number of
leaves of 22 by the GE90 was reduced to
18; reduced quality. Composite fan blades in the B777 passenger aircraft has
undergone stringent tests (10 years, only replaced 3
times). Blade leading edge and tip, using a titanium
sheath.
Tenon at the blade root, using a Teflon wear pads, so
after the leaves put into the dovetail slot without adding
lubricant. GENX engine fan case is made from composite materials
processing, with bands of woven composite materials similar to the
structure of mat. This is the first 1 to composite materials for large
engine casing. Composite Case inclusive properties and strength are
better than the metal casing and metal casing of the casing lighter
than 154 kg, an aircraft can reduce the quality of 363 kg, and will
not be corrosion, easy to maintain. Also in the middle of the fan and there are three
high-pressure compressor booster compressor, used to increase the
core engine flow.
High-pressure compressor: The more blisk
10 high pressure compressor pressure ratio is 23.0, the
average level pressure ratio is 1.368, with GE's GE90 engine level,
but leaves the technical design of a new generation of
three-dimensional flow, increasing the surge
margin. The first stage compressor with 1,2,5 blisk make GENX
engine used in a commercial engine more blisk series
engine. And most high-bypass ratio turbofan engines, like, GENX
engine high pressure compressor made from three double-play
receiver; outer casing as a bearing casing, inner casing ring as
inclusive air channel.
In order to restore engine performance, generally using a
special spray device, according to engine performance degradation
of the situation, the engine spray (cleaning fluid and water)
cleaning. In the GENX engine, using a built-in water cleaning
device, that is, high-pressure compressor were installed before the
circle of cloth with a spray nozzle 4; each nozzle jet spreading
angle is large, all over the import of high-pressure compressor
ring belt, spray washing is better. Engine 200 ~ 500 per work cycle, as appropriate, determine
the need for spraying. Under the slow jet cleaning fluid, cleaning wash water no
longer be required after the cleaning takes about 30 minutes once
the engine of other time-consuming and normally takes four
hours.) GENX engine is the first built-in sprinkler installation
of the engine.
Apart from the rear to see some of the GENX
engine. Small map (left) GENX unique combustion chamber, which has
a double loop with a Cyclone single ring premixed combustion
chamber to improve combustion efficiency. Small (right) for GENX turbine, which uses the high and
low pressure turbine reverse design, to improve
efficiency.
Combustion chamber: use of double loop premixed
swirler
GE90 engine combustion chamber for the double ring
cavity. The GENX engine for the conventional single-ring cavity
chamber, but with a double loop premixed cyclone, and the
application of lean design. In general the combustion chamber, there are high
temperature gas close to the flame tube wall, therefore, requires
the flame tube cooling on the large number of open slots or holes
(such as fire extinguishers on the GE90 engine has thousands of
holes.)
Premixed with double loop in the single ring cavity
cyclone chamber, the air swirl within the combustion zone wrapped,
the highest temperature areas are the core of the flame tube,
therefore, lower the flame tube wall temperature, without opening a
number of cooling holes. After the adoption of such a unique design, oil - gas
mixture burning completely, GENX engine combustion chamber is much
lower than the air discharge standard value of environmental
protection.
Turbo: from the military with high and low pressure
turbine reverse design
GENX engine has 2 high-pressure turbine and the seven
low-pressure turbine (GENX-2B engines for
six). High-pressure turbine blades using GE's 2nd generation
three-dimensional flow technology design and use of advanced design
and the latest cooling technology high temperature materials, the
cooling air to reduce life expectancy. Low-pressure turbine blades using the "special high-lift"
design, and the use of three-dimensional flow technology to design
the shape of the end wall, so that leaves reduced efficiency of
about 0.34%.
High and low pressure turbines turn in the opposite of
this design stems from military engines. F119 engine used on the switch to the first design (the
Chinese style is too large-thrust afterburning turbofan engine also
uses a high-pressure rotor of the transfer technology); and in the
civil engine for the A380 aircraft's Trent 900 engine used in this
first types of design (high pressure turbine on the
turn). GENX engine also adopts this reversal design, reducing
part count and improve efficiency.
GENX engine technology by GE, a long-term accumulation and
use of many innovative technologies into the commercial high bypass
ratio turbofan engine in one of the most advanced
models. Currently, the commercial aviation equipment, high bypass
ratio turbofan engine has been the United States as well as GE and
Pratt & Whitney Rolls-Royce dominated the
UK. Compared to other developed countries, basically only have
the air of 15 tons thrust high bypass ratio turbofan engine
development capabilities, these three giants have a monopoly in the
30-50 tons of large thrust thrust turbofan engine market, we can
see where the technology gap how insurmountable.
Engine industry in China in recent years pre-research,
technology validation and model development and other aspects of
rapid development. However, because of a late start in the high bypass ratio
turbofan engines, China is still not have their own engine
models. Still has only IL-76 transport aircraft in the imitation
stage with D30 engine, and this engine indexes only the 120-130 kN
thrust class, with the GENX engine thrust differ
greatly. Moreover, with the rapid development of technology,
continuous improvement of the domestic market demand (especially
raised large transport aircraft program) and the increasingly
fierce international competition in the market engine industry in
China poses a severe challenge.