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An F1 Engine Design
The engine is the heart of an F1 car. To fans who enjoy the distinctive
sound, smell, vibration and sheer speed produced by an F1 engine is
at once addictive and powerful feeling. For the F1 engine manufacturers,
armies of engineers and technicians bang themselves day in and day out
to push the envelope in materials, design, and computer measurement
and control. ON average a team comes up with around 200 engines per
year, each engine are hand made and takes up over 80 hours and last
just about 400 hours. The engine in an F1 car is part of the chassis
structure and therefore must absorb some of the forces produced by the
rear suspension. Reliability is a key concern for all engine manufacturers.
On a typical race weekend in Europe, every team brings about 10 engines
and 28 people which includes race engineers who fine-tune the engine
for every part of the track and software specialists to look after the
hundreds of sensors associated with the complex engine management system.
Although the solutions to producing a winning engine are shrouded in
secrecy, the basic design parameters for a modern F1 engine are well
understood. The engine's centre of weight should be as low as possible,
some teams like Renault in 2001 went with 110 degrees V angle to lower
the engine to the track. The production of torque/power needs to be
smooth and responsive across the largest possible rev range, the dimensions
of the engine should be as compact as possible, and it needs to be reliable
in the harsh racing environment.
Weight and Dimensions (FIA Specification)
The engine weight is 600kg minimum including driver which consists of
oil and a full tank of fuel which makes up one-quarter of the entire
weight of the car. The key to using this weight to an advantage has
to do with how it is distributed. For stability reasons, to minimise
pitch under acceleration/braking and roll during cornering, the engine's
centre of weight should be as low as possible, or close to the height
of the wheel axles. This is one of the key reasons engine manufacturers
are investigating greater than 90( cylinder angles in the V configuration,
but vibration is a major problem that has to be overcome in this design.
The design of the engine ultimately impacts the chassis especially aerodynamic
characteristics of the rear of the chassis, but to a large extent, will
dictate the aerodynamic requirements of the front. Providing clean air
flow to the radiator intakes and air box is key to getting the best
performance out of the engine.
Power
A smooth or consistent delivery of power is crucial for enabling the
driver to place the car continually on the edge of traction and avoid
sliding or spinning out. This translates to a flat torque curve, ie
a constant production of torque across the useful rev range, and therefore
a linear power curve (power being equal to torque multiplied by rpm).
To ensure the responsiveness of the engine (easy to accelerate/decelerate),
the inertia of the rotational components such as the pistons and crankshaft
should be minimised. Utilizing light weight materials are essential,
but can have detrimental effects on low-end torque, combined with increased
frictional losses, the limit on high rpm rev due to the inability to
handle the increasing forces and stresses. Engineers stress many factors
to manage efficient engine torque/power which includes the pipes of
the exhaust system(individually tuned in length), diameter and curvature
(minimise blockage and ensure that the gases to/from the cylinders do
not interfere with each other).
The air box above the driver's helmet must provide a constant pressure
and speed of air intake regardless of outside weather conditions, at
all parts of the track including tight corners. Losses of energy due
to vibrations, heat loss and friction must be minimised. Complex computer
modelling and simulation is carried out to constantly improve every
aspect of performance. In this case, computer-intensive CFD (Computational
Fluid Dynamics) is use to develop the aerodynamics of the car to simulate
the ignition, flame propagation and gas flow inside the cylinders.
Reliability
An F1 engine is designed to run 400km before being overhauled. Thus,
the stress it goes through is by no means easy, it has to withstand
heat, g-forces and maximum rpm (far exceed that experienced by a commercial
engine during its lifetime). Periodic factory tests are unable to fully
simulate the g-forces, airflow/cooling characteristics, and track surface
vibrations encountered in racing, track testing is still invaluable
as a source of information when looking at reliability.
Engineers use telemetry data to gather test results that retrieves important
information in conjunction with engine components. Every components
of the engine and factors are studied. In addition, the two-way telemetry
or Bi-Telemetry technology is also used to maximise reliability by allowing
the team to limit the engine's rev range (switch in the spare oil reservoir
if needed).
Mapping, where the engine's performance requirements for every metre
of track are input to the engine management system, helps increase reliability.
This procedure ensures that all engine set-up parameters are optimised,
thus minimising unnecessary stresses on the engine components. Life
expectancy of engine components like cylinder heads lasts longer than
others and are recycled for engines to be used in testing, practice
and qualifying sessions. In other words, recycled engines, but for Grand
Prix races, each engine is brand new.
Numbers on a typical race per Grand Prix
Number of combustions in a GP: 8 million
Number of engine & vehicle measurements/second at top speed: 150,000
Maximum rpm: 19,000+
Number of individual parts: 5,000 approx
Number of different parts: 1,000 approx
Maximum exhaust temperature(in a race): 800 celcius
Number of litres of air aspirated in 1 second at top speed: 450
F1 engines built in a year: 200
Weight in kg: <100
Engine assembly hours: 80
Hours checking a new cylinder head with computer tomography: 20
Number of engines brought to each GP: 10
The Editor pitstop.com.my
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