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From the
Pressbook: the Design of the BMW P84
BMW P84 - power and endurance required. Times
are changing. While the "short burner" delivers extra power and used
to provide a sensation for a single qualifying lap in Formula One,
there is now a need for long-life power units. The Formula One
Sporting Code introduced by the FIA for the 2004 season stipulates
the use of a single engine for each vehicle over the entire Grand
Prix weekend. This increases the required duration of an engine to
800km. It doubles the distance covered by engines competing in the
2003 season, where the same engine was already being used for
qualifying and racing. This represents a considerable challenge for
BMW engineers.
Mario Theissen encapsulates the new requirement
in a simple equation: "If an engine has to have a longer service
life, every component must in principle be designed to be tougher.
This means that the engine will get bigger and heavier, and that is
at the expense of revolutions and hence power. Minimizing these
losses while guaranteeing endurance are the goals we have to work
towards."
Early start to development and early testing.
The BMW P84 was developed by the team of engineers led by Heinz
Paschen, Head of BMW F1 Development, in close co-operation with the
specialists from the BMW Research and Innovation Center (FIZ). It
has been tailor made for the regulation requirements of the 2004
season.
Work on the new BMW engine began in Munich even
earlier than in previous years. The team of engineers already
started working on a specification for the engine powering the 2004
season in November of 2002. In May 2003, the first version of the
P84 was up and running on the test rig in Munich. Over the coming
weeks, a number of other versions of the BMW P84 came on stream.
Paschen says, "The key factor here was to prove 'fit' for the
increased running distance". The version of the engine finally
intended for the FW26 was put on the test rig for the first time in
July 2003 before being tested in an interim car at Monza on 4
September. From October, work focused on final link-up with the
chassis, and circuit testing continued in November.
Specification
and priorities for 2004
The design of the BMW P84 engine is based on its
predecessor, but every single component was affected by the new
specifications. The engine's design priorities for the 2004 season
are: the same dependability must be guaranteed for significantly
longer running times while sacrificing as little performance as
possible. Material specialists at the BMW Research and Innovation
Center also helped to ensure that the effect on dimensions and
weight was kept to a minimum, by developing the new heat-treatment
procedures that enhanced endurance properties.
Paschen adds that "We were already so geared up
in quality control with the processes that had been running in 2003
that the non-conformance quota in testing and racing was reduced
drastically." The final endurance tests on the dynamic test rig is
once again carried out using the Monza circuit profile because at
73%, this track has the highest full-throttle section. However,
qualification for use was increased over 800 kilometers.
Revolutions
yesterday and tomorrow
The BMW P82 was the engine used by the BMW
WilliamsF1 Team in the 2002 season. The last version of this engine
achieved revs of 19,050 per minute. For the following season, new
regulations were introduced for 2003 including no engine changes
permitted between qualifying and racing.
The duration requirement of an engine, including
the race distance, was increased therefore to around 400 kilometers
by the flying lap on Saturday. "On paper, that's not too big an
increase", explains Theissen, "But it involves a more complex load
profile for the engines. It's rather like sending a marathon runner
in to run a sprint just before the race starts." Despite these new
endurance specifications, BMW succeeded in achieving further
increases in engine speed and performance. During the final race of
the season in Japan, the BMW P83 clocked up an impressive 19,200 rpm
and delivered well above 900 bhp. And it was also a model of
reliability. The only engine damage during the 2003 season was
sustained in the Austrian Grand Prix. This was due to a water leak
in the cooling circuit. Theissen recalls that, "Without cooling
water, even the best engine in the world isn't going to get very
far".
Theissen is expecting an overall reduction in
engine speed and says, "At the start of 2003, I would have guessed
at a reduction of 10 percent for 2004. We're now reckoning on less".
From 2004, BMW
engineering is no longer restricted to the engine
The expanded co-operation between BMW and
WilliamsF1 will see the experts in Munich extending their support
for their partners in Grove in some areas of gearbox, electrical and
electronic systems, and aerodynamics. This will take the mutual
spin-offs derived from Formula One and volume production in the BMW
Research and Innovation Center beyond the engine. The gearbox casing
and other components will be manufactured at BMW. The BMW Research
and Innovation Center will be working on aerodynamic development in
the area of simulation and calculation.
Synergies
between F1 and volume-production development
"The Formula One project is a massive technology
laboratory for BMW", comments Theissen. "The main reason for our
company re-entering Formula One was to benefit from synergy effects
that arise between development for Formula One and volume
production", he confirms.
One thing was clear right from the start. The
BMW engines for the world's most advanced racing were going to be
developed and manufactured in Munich - in the cradle of the parent
company. The BMW Technology and Innovation Center would play a key
role in this process. The Formula One manufacturing facility was set
up less than one kilometer away from this think-tank, and the two
are fully integrated. "The BMW Research and Innovation Center
represents the future of BMW", explains Theissen. "That's where the
most highly skilled engineers are working in high-tech research and
development facilities. The BMW Research and Innovation Center has
massive resources and we benefit from these resources directly.
Correspondingly, the extreme technical requirements of Formula One
involvement and the fast development speed constitute a unique test
bed for our engineers."
BMW has turned the vision of a seamless process
chain into reality at a dedicated facility - from conception,
through design, casting, manufacture of components, setup and test
phase through to dedicated electronic engine management. This system
eliminates transport paths, and all the know-how developed can flow
into volume production.
Casting
technology and manufacture
The casting quality of the engine block,
cylinder head and gearbox largely determines the performance and
endurance of the power unit. Leading-edge casting technologies with
maximally precise process management yield lightweight components
with very high stiffness. In order to safeguard these qualities, BMW
has a foundry in Landshut to cast components for vehicles
manufactured in volume production. A dedicated Formula One casting
facility was added in 2001. Theissen adds that, "The two departments
work under joint management. This guarantees ongoing exchange of
information".
Oil sumps for the M3, M5 and Z8 models and the
intake manifold for the eight-cylinder diesel engine are using the
same sand casting procedure used for the Formula One V10.
A Formula One parts manufacturing facility was
set up alongside the facility
for volume components almost at the same time as the Formula One
foundry. The Formula One team manufactures camshafts and crankshafts
for the BMW P84 in the same location.
WilliamsF1 is meanwhile also benefiting from the
work of the two departments. The aluminium gearbox casing for the
FW26 is being manufactured in a sand casting process in Landshut and
other gearbox components come from BMW Formula One production.
Gearwheels are produced in Dingolfing in parallel with volume
production.
Electronics in
Grand Prix racing and on the road
Engine management is subject to immense demands
by an engine which races at 19,000 rpm while still having to be
driveable at low revs. Ignition timing and fuel supply must be
perfectly tuned to the order of milliseconds in order to achieve
optimum efficiency - maximum power for minimum fuel consumption. Low
consumption means improved lap times and more flexibility for racing
strategy. Aside from engine management, onboard electronics are also
responsible for monitoring all functions.
The expertise of the electronics specialists at
the BMW Research and Innovation Center gave BMW the confidence to
develop its own Formula One engine management systems instead of
having to resort to racing specialists. Engineers who normally
design the onboard electronic systems for the BMW M3 and M5 models
have also developed the engine management system for Formula One
engines. The expertise they gain in this field flows back into
volume production. Top BMW models like the 7 Series and the M Series
cars already have two microprocessors that BMW first deployed and
tested in Formula One. Memory technology previously used
successfully in Formula One has also been deployed for Internet
access and the navigation system in the BMW 7 Series. Theissen adds
that, "When it comes to monitoring functions, we are also gaining
knowledge that can be used for road vehicles. Timely warnings and
automated electronic intervention are also relevant to safety there,
and they protect vehicles against damage".
Other automated technology originated in Formula
One is also being used in the BMW M3. The "Sequential M Gearbox -
SMG with DRIVELOGIC" and the "acceleration assistant" owes its
origins to Formula One. The SMG drive concept offers F1 gearbox
technology for everyday operation. Drivers can change gear
electronically using a paddle behind the steering wheel. Just like
in Formula One, an electrical hydraulic system replaces the
mechanical clutch and gearshift procedure, and the drivers operating
the SMG system can also change gear while their foot remains on the
accelerator. The "acceleration assistant" is an automatic system
which allows drivers to move off from rest with programmed,
regulated slip. This is comparable with the launch control familiar
from Formula One.
Material
development and model construction
As lightweight as possible and as robust as
necessary - the credo of engine design reaches its highest
interpretation in the Formula One. Anyone who sets too much store by
safety will have too much ballast on board. Material research at the
BMW Research and Development Center delivers important initiatives
for BMW Formula One engine development. For example, lightweight
alloys are continually being developed and tested. Aerospace is
frequently the starting point for these developments. A number of
very promising discoveries have already been used in the BMW Formula
One engine. They have not yet been considered for production
vehicles because of the need for high volumes. Theissen explains
that, "They are undergoing further testing there and the opportunity
of using these new materials allows helps engineers to develop them
for road car production".
Short reaction times are the key to success in
the unrelenting rhythm of a Formula One season. This is true for
continuous development of the engines and for overcoming problems.
New solutions demand new designs and new tools - a very
time-consuming manufacturing process with no guarantee of success.
In order to shorten this lead time, the BMW F1 team can approach the
Department of Rapid Prototyping/Tooling Technology at the BMW
Research and Innovation Center and it is able to intervene and
shorten this period. As soon as the necessary parts have been drawn
on the CAD CAM systems, computer-controlled machines produce scale
models made of resin, plastic powder, starch or wax using laser
beams or three-dimensional pressure engineering. This means that it
is quickly possible to simulate installation situations and
interactions, allowing modifications to be implemented before the
final manufacturing process begins.
