May 2010 covers_Covers.qxd - World Airnews

Further military action in the Middle
East could destabilise the situation and
lead to price rises that could well surpass
$200 per barrel and this would lead to a
reduction in air travel and highlight the
need for even greater fuel conservation
and then be a boost for alternative fuels.
ENTER THE EFE
Meanwhile, enter the environmentally
friendly engine (EFE) an example of which
is about to begin testing at a Rolls-Royce
facility. Rolls-Royce embarked on a series
of programmes using private venture,
MoD, DTI and EU funding sources.
The EFE programme is a critical element
in the overall technology acquisition
and validation process to achieve industry
targets and in order to develop the UK
aerospace industry, funding for this programme
is being sought entirely from
within the UK.
The key technologies are high temperature
materials, high efficiency turbine components,
low emissions combustion,
advanced manufacturing technologies, engine
controls and actuation technologies
and nacelle aerodynamic technologies.
Engine cores can be designed to be
smaller and lighter thanks to new materials
and higher pressure ratios and temperatures.
The smaller core can allow
higher by-pass ratios with both a reduction
in fuel consumption and noise.
These are typical parameters for the
EFE where they can be tested and even
retrofitted into existing engines to some
extent. Rolls-Royce is on record as saying
that the EFE programme is expected to introduce
technologies that could be operational
within ten years.
The first EFE is a modified Trent 1000,
though it lacks fan blades. Work will concentrate
on combustor and turbine developments
and is expected to run some 100
to 150 degrees hotter than current engines.
It is a collaborative programme including
Bombardier Aerospace, HS Marston
Aerospace, Unison Engine Components
and Aero Engine Controls. This lastnamed
company is a joint venture between
Rolls-Royce and Goodrich
Corporation. No doubt, an early recipient
of the emerging technology will be the
Trent XWB engine being developed for
the Airbus A350XWB.
Meanwhile, wind tunnel testing of multiple
configurations of sub-scale blades for
GE’s open rotor engine is being conducted
to identify the optimum blade design for
the engine’s two counter-rotating stages
of blades. Minimal noise output and min-
CFM International has carried out successful tests on a CFM-56 engine using an ester type biofuel
imal specific fuel consumption, (with the
associated lower emissions output) are
primary benefits derived from the optimum
blade configuration (see World
Airnews, October 2009).
Open rotors cause some concern over
the problem of noise. Subsequent acoustic
testing, still ongoing, has involved complex
blade configurations that reflect the technological
advances of the past 20 years, in
areas such as inter-blade spacing, blade
sweep angle and chord length and in other
features derived through three-dimensional
aerodynamic (3-D aero) design.
Rolls-Royce has expressed interest and
confidence in the open rotor concept,
though it has said little about its own developments.
CFM International also is exploring
the open rotor, though admitting
some concern over the noise problem.
Pratt & Whitney already has something
to shout about and is currently touting
the geared turbofan.
This company’s PurePower PW1000G
geared turbofan, due to enter service in
2013, will provide a 12 to 15 percent fuel
efficiency over current turbofans and will,
no doubt, improve on those figures in
service as experience and technology is
accumulated.
Pratt & Whitney’s PurePower 1000G
WORLD AIRNEWS, MAY 2010. 21