Kinetic Energy Recovery System1. INTRODUCTIONKERS means Kinetic
Energy Recovery System and it refers to the mechanisms that recover
the energy that would normally be lost when reducing speed. The
energy is stored in a mechanical form and retransmitted to the
wheel in order to help the acceleration. Electric vehicles and
hybrid have a similar system called Regenerative Brake which
restores the energy in the batteries.The device recovers the
kinetic energy that is present in the waste heat created by the
cars braking process. It stores that energy and converts it into
power that can be called upon to boost acceleration.
There are principally two types of system - battery (electrical)
and flywheel (mechanical). Electrical systems use a motor-generator
incorporated in the cars transmission which converts mechanical
energy into electrical energy and vice versa. Once the energy has
been harnessed, it is stored in a battery and released when
required.
Mechanical systems capture braking energy and use it to turn a
small flywheel which can spin at up to 80,000 rpm. When extra power
is required, the flywheel is connected to the cars rear wheels. In
contrast to an electrical KERS, the mechanical energy doesnt change
state and is therefore more efficient.
There is one other option available - hydraulic KERS, where
braking energy is used to accumulate hydraulic pressure which is
then sent to the wheels when required.
2. CONSTRUCTION DETAILSThe first, mechanical, consisted of using
a carbon flywheel in a vacuum linked via a CVT transmission to the
differential. This system stores the mechanical energy, offers a
big storage capacity and has the advantage of being independent
from the gearbox. However, to be driven precisely, it requires some
powerful and bulky actuators, and lots of space. Compared to the
alternative of electrical-battery systems, the mechanical KERS
system provides a significantly more compact, efficient, lighter
and environmentally-friendly solution.The components within each
variator include an input disc and an opposing output disc. Each
disc is formed so that the gap created between the discs is
doughnut shaped; that is, the toroidal surfaces on each disc form
the toroidalcavity. Two or three rollers are located inside each
toroidal cavity and are positioned so that the outer edge of each
roller is in contact with the toroidal surfaces of the input disc
and output disc. As the input disc rotates, power is transferred
via the rollers to the output disc, which rotates in the opposite
direction to the input disc.The angle of the roller determines the
ratio of the Variator and therefore a change in the angle of the
roller results in a change in the ratio. So, with the roller at a
small radius (near the centre) on the input disc and at a large
radius (near the edge) on the output disc the Variator produces a
low ratio. Moving the roller across the discs to a large radius at
the input disc and corresponding low radius at the output produces
the high ratio and provides the full ratio sweep in a smooth,
continuous manner.The transfer of power through the contacting
surfaces of the discs and rollers takes place via a microscopic
film of specially developed long-molecule traction fluid. This
fluid separates the rolling surfaces of the discs and rollers at
their contact points.The input and output discs are clamped
together within each variator unit. The traction fluid in the
contact points between the discs and rollers become highly viscous
under this clamping pressure, increasing its stickiness and
creating an efficient mechanism for transferring power between the
rotating discs and rollers.The second option, electrical, was to
rely on an electrical motor, which works by charging the batteries
under braking and releasing the power on acceleration. This system
consists of three important parts:1. An electric motor (MGU: Motor
Generator Unit) situated between the fuel tank and the engine,
linked directly to the crankshaft of the V8 to deliver additional
power.2. Some latest generation ion-lithium batteries (HVB: High
Voltage Battery Pack) capable of storing and delivering energy
rapidly.3. A control box (KCU: KERS Control Unit), which manages
the behavior of the MGU when charging and releasing energy. It is
linked to the cars standard electronic control unit.In essence a
KERS systems is simple, you need a component for generating the
power, one for storing it and another to control it all. Thus KERS
systems have three main components: The MGU, the PCU and the
batteries. They are simply laid out as in the diagram below:
Fig 1.0 Schematic Assembly Of KERS in a F1 car2.1 MGU (Motor
Generator unit) Mounted to the front of the engine, this is driven
off a gear at the front of the crankshaft. Working in two modes,
the MGU both creates the power for the batteries when the car is
braking, then return the power from the batteries to add power
directly to the engine, when the KERS button is deployed. Running
high RPM and generating a significant Dc current the unit run very
hot, so teams typically oil or water cool the MGU. Fig 1.1Marelli
MGU as used by Ferrari Fig 1.2 Marelli prototype PCU
2.2 BatteriesDuring the 2009 season only electrical batteries
were used, although at least two flywheel systems were in
development, but unraced. We will focus on the arrays of
lithium-ion batteries that were raced. Made up of around 40
individual cells, these batteries would last two races before being
recycled. In McLarens case these were mounted to the floor in the
sidepods beneath the radiators. Other teams mounted them in a false
bottom to the fuel tank area for safety in the event of a crash.
Being charged and discharged repeatedly during a lap, the batteries
would run very hot and needed cooling, this mainly took the form of
oil or water cooling, and again McLarens example had them pack
water cooled with its own pump and radiator.
2.3PCU (Power Control Unit)Typically mounted in the sidepod this
black box of electronics served two purposes, firstly to invert
& control the switching of current from the batteries to the
MGU and secondly to monitor the status of the individual cells with
the battery. Managing the battery is critical as the efficiency of
a pack of Li-ion cells will drop if one cell starts to fail. A
failing cell can overheat rapidly and cause safety issues. As with
all KERS components the PCU needs cooling.3.KERS in Formula 1The
FIA (Federation InternationaleL"Automobile) have authorized hybrid
drivetrains in Formula 1 racing for the 2009 racing season. The
intent is to use the engineering resources of the Formula 1
community to develop hybrid technology for use not only in
motorsport but also eventually in road vehicles. The hybrid systems
specifications have been kept to a minimum, especially the type of
hybrid system. This was done purposely to lead to the study and
development of various alternatives for electrical hybrids which
has been met with success. The FlybridKinetic Energy Recovery
System (KERS) was a small and light device designed to meet the FIA
regulations for the 2009 Formula One season. The key system
features were: Aflywheel made of steel and carbon fibre that
rotated at over 60,000 RPM inside an evacuated chamber The flywheel
casing featured containment to avoid the escape of any debris in
the unlikely event of a flywheel failure The flywheel was connected
to the transmission of the car on the output side of the gearboxvia
several fixed ratios, a clutch and theCVT 60 kW power transmission
in either storage or recovery 400 kJ of usable storage (after
accounting for internal losses) A total system weight of 25 kg A
total packaging volume of 13 litres
The layout of the device was tailored exactly to meet the
customer's requirement resulting in a truly bespoke solution that
fitted within the tight packaging constraints of a F1 car. The
mechanical KERS system utilises flywheel technology developed by
Flybrid Systems to recover and store a moving vehicles kinetic
energy which is otherwise wasted when the vehicle is decelerated.
With a focus on safety, the FIA have specified a limit on both the
power rating of the hybrid system at 60kW and the quantity of
energy transfer per lap at 400kJ. This translates into an extra
85bhp for just under seven seconds, which makes overtaking another
vehicle on the track easier and the race much more interesting.Thus
although a 0.3s boost to laptimes, the system was ultimately
limited in its potential to improve laptimes. Thus no team could
create a competitive advantage from a more powerful system. Then
the weight of the system created issues, At a time when the wider
front slick tyres demanded an extreme weight distribution of up to
49% weight on the front axle, the 25+Kg of a KERS system mounted
behind the Centre of gravity, the handicapped teams being able to
push weight forwards. Most teams dropping or not racing their
system cited weight as the main reason for its loss. The 60kW/400kJ
limits in Formula 1 will not apply to road cars. Road cars will
safely have more power and energy transfer due to their larger
weight when compared with racecars, which will provide them with
significant benefits. There is more than one type of KERS used in
motorsports. The most common is the electronic system built by the
Italian company MagnetiMarelli, which is used by Red Bull, Toro
Rosso, Ferrari, Renault and Toyota. Although races have been won
with this technology, KERS was removed from the 2010 Formula 1
season due to its high cost. Fig 2.1.FlybridKinetic Energy Recovery
System Fig 2.2.A KERS flywheel
3.1. AncillariesAside from these main components the KERS system
also integrates with the FIA Security in order to control and
monitor the PCU. KERS has to be driver activated; this is achieved
from a steering wheel button. Although the drive has to initiate
the KERS boost, the teams set the system up such that the driver
knows to engage the system out of specific corners, the system then
delivers the predetermined amount of boost specific to the demands
of that section of track. In practice the KERS systems is being
charged and discharged to this preset map of activations, which
smoothens the balance between charging and discharging, so the
system does not overcharge above the regulatory limit. Again the
SECU ensures no more than the capped amount of energy is delivered
each lap.
Fig 3. KERS Schematic
Sensors:boost button, brake sensor
Actuators:electric motor/generator unit, continuously variable
transmission, flywheel, electro-hydraulic system, clutch.
Data Communications:CAN Bus.
Manufacturers:Bosch Motorsport, Flybrid Systems, MagnetiMarelli,
Williams Hybrid Power, Zytek Group.
4. TYPES OF KERSAdvanced transmissions that incorporate hi-tech
flywheels are now being used as regenerative systems in such things
as formula-1 cars, where they're typically referred to as kinetic
energy recovery systems (KERS). The types of KERS that have been
developed are:4.1. Mechanical KERS4.2. Electro-mechanical KERS4.3.
Hydraulic KERS4.4. Electronic KERS
Of the three types of KERS units mechanical, electrical and
hydraulic Formula 1 teams have decided to go for the mechanic one.
The reasons behind this choice are quite logical: less weight,
better weight distribution, increased power boost and improved fuel
economy.
4.1. Mechanical KERSThe mechanical KERS system has a flywheel as
the energy storage device but it does away with MGUs by replacing
them with a transmission to control and transfer the energy to and
from the driveline. The kinetic energy of the vehicle end up as
kinetic energy of a rotating flywheel through the use of shafts and
gears. Unlike electronic KERS, this method of storage prevents the
need to transform energy from one type to another. Each energy
conversion in electronic KERS brings its own losses and the overall
efficiency is poor compared to mechanical storage. To cope with the
continuous change in speed ratio between the flywheel and
road-wheels, a continuously variable transmission (CVT) is used,
which is managed by an electro-hydraulic control system. A clutch
allows disengagement of the device when not in use.As Li-ion
batteries are still an expensive emerging technology, plus they
have associated risks, recycling and transport problems. The
attraction of flywheel KERS is obvious, however no team have raced
such a system in F1. Flywheels can effectively replace the Li-ion
batteries with in a typical KERS system, the flywheel being mated
to a second MGU to convert the power generated by the primary MGU
on the engine into the kinetic to be stored in the flywheel.
Williams are believed to have just such a system. However the
simper flywheel solution is connect the flywheel system via a
clutched and geared mechanism.
4.2. Electro-mechanical KERSIn electro-mechanical KERS energy is
not stored in batteries or super-capacitors, instead it spins a
flywheel to store the energy kinetically. This system is
effectively an electro-mechanical battery. There is limited space
in a racecar so the unit is small and light. Therefore, the
flywheel spins very fast to speeds of 50,000 - 160,000 rpm to
achieve sufficient energy density. Aerodynamic losses and heat
buildup are minimized by containing the spinning flywheel in a
vacuum environment. The flywheel in this system is a magnetically
loaded composite (MLC). The flywheel remains one piece at these
high speeds because it is wound with high strength fibers. The
fibers have metal particles embedded in them that allows the
flywheel to be magnetized as a permanent magnet. The flywheel will
perform similarly to an MGU. As the flywheel spins, it can induce a
current in the stator releasing electricity or it can spin like a
motor when current flows from the stator. This flywheel is used in
conjunction with an MGU attached to the gearbox which supplies
electrical energy to the flywheel from the road and returns it to
the gearbox for acceleration at the touch of a button. Not all
flywheels used in the electro-mechanical KERS are permanent
magnets. Instead, these systems use two MGUs, one near the flywheel
and another at the gearbox. Some systems use flywheels and
batteries together to store energy.
4.3. Hydraulic KERSA further alternative to the generation and
storage of energy is to use hydraulics. This system has some
limitations, but with the capped energy storage mandated within the
rules the system could see a short term application. Separate to
the cars other hydraulic systems, a hydraulic KERS would use a pump
in place of the MGU and an accumulator in place of the batteries.
Simple valving would route the fluid into the accumulator or to the
pump to either generate or reapply the stored power. Hydraulic
accumulators are already used in heavy industry to provide back up
in the event of failure to conventional pumped systems.
Using filament wound carbon fibre casing, an accumulator of
sufficient capacity could be made light enough to fit into the car.
They might be capped in terms of practical storage with in the
confines of an F1 sized system, but McLaren had prepared just such
an energy recovery system back on the late 90s, but it was banned
before it could race. With the relatively low FIA cap on energy
storage, just such a system could be easily packaged, the hydraulic
MGU would be sited in the conventional front-of-engine position and
the accumulator, given proper crash protection fitted to the
sidepod. Saving space would be minimal control system (equivalent
to the PCU) as the valving to control the system could be
controlled by the cars main electro hydraulic system. McLaren have
recently been quoted as saying the 2011 KERS would be more
hydraulic and less electronic giving rise to speculation that a
hydraulic storage system could be used.An older technology than
that of the kinetic steering wheels and batteries to create KERS
for trucks: A hydraulic fluid.The HLA (Hydraulic Launch Assist)
developed by Eaton is located between the transmission and the back
axis of the truck. When the driver steps on the brake, it uses the
movement of the wheels to compress hydraulic fluid, thus reducing
the trucks speed. When the truck accelerates again, the energy
returns to the wheels. This is a hydraulic recovery system. The
principle behind hydraulic KERS units, by contrast, is to reuse a
vehicles kinetic energy by conducting pressurized hydraulic fluid
into an accumulator during deceleration, then conducting it back
into the drive system during accelerationThis system can save up to
30% on fuel in trucks that make numerous stops such as garbage
trucks. In addition brakes have a larger life span, five times more
than a simple diesel-electric hybrid, which increases the weight of
the truck by about half a ton. But there are some fundamental
problems here as well. One is the relatively low efficiency of
rotary pumps and motors. Another is the weight of incompressible
fluids. And a third is the amount of space needed for the hydraulic
accumulators, and their awkward form factor. None of this matters
too much in, say, heavy commercial vehicles but it makes this
option unsuitable for road and racing cars. Fig 4.1.Carbon Fibre
Hydraulic Accumulator Fig 4.2. HLA (Hydraulic Launch Assist)
4.4. Electronic KERSIn electronic KERS, braking rotational force
is captured by an electric motor / generator unit (MGU) mounted to
the engines crankshaft. This MGU takes the electrical energy that
it converts from kinetic energy and stores it in batteries. The
boost button then summons the electrical energy in the batteries to
power the MGU. The most difficult part in designing electronic KERS
is how to store the electrical energy. Most racing systems use a
lithium battery, which is essentially a large mobile phone battery.
Batteries become hot when charging them so many of the KERS cars
have more cooling ducts since charging will occur multiple times
throughout a race. Super-capacitors can also be used to store
electrical energy instead of batteries, they run cooler and are
debatably more efficient.5. KERS & Regenerative BrakingSince
kinetic energy is the energy of motion, you could probably guess
that cars create lots of it. Capturing some of that kinetic energy
for the sake of fuel efficiency in a hybrid car is a little tricky,
but regenerative braking is one common method employed by many
automakers.On a non-hybrid car during a routine stop, mechanical
braking slows and then stops the vehicle. For instance, if your
vehicle has disc brakes, the brake pads clamp down on a rotor to
stop the car. If your car has drum brakes, the brake shoe pushes
the brake lining material outward toward the brake drum surface to
slow or stop the car. In both cases, most of the kinetic energy in
the spinning wheels is absorbed by the pads or the drums, which
creates heat.On a hybrid car that uses regenerative braking, the
electric motor is used to slow the car. When the motor is operating
in this mode, it acts as a generator to recover the rotational
kinetic energy at the wheels, convert it into energy and store it
in the car's batteries. When the driver of the hybrid car takes his
or her foot off of the accelerator pedal, the resistance provided
by the generator slows the car first and then the mechanical brake
pads can be applied to finish the job. Of course, the mechanical
brake pads can also be engaged immediately in an emergency braking
scenario.The car uses the energy stored in the battery to power the
electric motor which drives the car at low speeds. Depending on the
type of hybrid, the electric motor can either work alone to move
the car or it can work in concert with the car's gasoline-powered
engine. So regenerative braking, coupled with eco-friendly driving
techniques like slow starts and slower overall vehicle speeds, is
an important feature on some of some of the most fuel-efficient
vehicles on the road today.Regenerative brakes may seem very
hi-tech, but the idea of having "energy-saving reservoirs" in
machines is nothing new. Engines have been using energy-storing
devices called flywheels virtually since they were invented.The
basic idea is that the rotating part of the engine incorporates a
wheel with a very heavy metal rim, and this drives whatever machine
or device the engine is connected to. It takes much more time to
get a flywheel-engine turning but, once it's up to speed, the
flywheel stores a huge amount of rotational energy. A heavy
spinning flywheel is a bit like a truck going at speed: it has huge
momentum so it takes a great deal of stopping and changing its
speed takes a lot of effort. That may sound like a drawback, but
it's actually very useful. If an engine (maybe a steam engine
powered by cylinders) supplies power erratically, the flywheel
compensates, absorbing extra power and making up for temporary
lulls, so the machine or equipment it's connected to is driven more
smoothly.The heavy metal flywheel attached to this engine helps to
keep it running at a steady speed. Note that most of the heavy
metal mass of the flywheel is concentrated around its rim. That
gives it what's called a high moment of inertia: it takes a lot of
energy both to make it spin fast and slow down. It's easy to see
how a flywheel could be used for regenerative braking. In something
like a bus or a truck, you could have a heavy flywheel that could
be engaged or disengaged from the transmission at different times.
You could engage the flywheel every time you want to brake so it
soaked up some of your kinetic energy and brought you to a halt.
Next time you started off, you'd use the flywheel to return the
energy and get you moving again, before disengaging it during
normal driving. The main drawback of using flywheels in moving
vehicles is, of course, their extra weight. They save you energy by
storing power you'd otherwise squander in brakes, but they also
cost you energy because you have to carry them around all the
time.Advanced transmissions that incorporate hi-tech flywheels are
now being used as regenerative systems in such things as formula-1
cars, where they're typically referred to as kinetic energy
recovery systems (KERS).
5.1. KERS dissimilar from Regenerative BrakingTraditional
hybrids acquire electrical energy from braking in a similar way
that electrical KERS equipped vehicles do but the difference lies
in how the energy is reused. While KERS quickly re-injects the
energy back into the powertrain to provide additional power boost
in conjunction with the engine, the traditional hybrid saves the
energy to power the electric power train. KERS is different from
traditional hybrids in that the stop start functionality is not a
prime goal of the system. KERS work very well in conjunction with
engine mounted Stop/Start systems, or it can be engine mounted and
used for stop start functionality. The KERS hybrid system cannot be
"charged" by the engine directly, which is the requirement that has
lead to its name, "KERS".6. CARMAKERS APPLICATION OF KERS
TECHNOLOGY6.1. PorscheAt 2011 North American International Auto
Show Porsche unveiled a RSR variant of their Porsche 918 concept
car which uses a flywheel-based KERS system that sits beside the
driver in the passenger compartment and boosts the dual electric
motors driving the front wheels and the 565 BHP V8 gasoline engine
driving the rear to a combined power output of 767 BHP.The electric
motors are not powered by a set of batteries, as in a traditional
hybrid, rather they take their power from an inertial flywheel
mounted where the passenger seat would be on a road car and
spinning at up to 36,000rpm. That's spun up by momentum when the
car brakes and, when the driver hits a button, that momentum is
converted to give an acceleratory boost.
Fig 5.1. Porsche 918 RSR Concept Car Fig 5.2. Ferrari Vettura
Laboratorio HY-KERS6.2. FerrariThe HY-KERSvettura
laboratorio(experimental vehicle) is an example of how Ferrari is
approaching the development of hybrid technology without losing
sight of the performance traits and driving involvement that have
always exemplified its cars.Weighing about 40 kg, the compact,
tri-phase, high-voltage electric motor of the HY-KERS is coupled to
the rear of the dual-clutch 7-speed F1 transmission. It operates
through one of the transmissions two clutches and engages one of
the two gearbox primary shafts. Thus power is coupled seamlessly
and instantaneously between the electric motor and the V12. The
electric motor produces more than 100 hp as Ferraris goal was to
offset every kilogram increase in weight by a gain of at least one
hp.Under braking the electric drive unit acts as a generator, using
the kinetic energy from the negative torque generated to recharge
the batteries. This phase is controlled by a dedicated electronics
module which was developed applying experience gained in F1 and, as
well as managing the power supply and recharging the batteries, the
module also powers the engines ancillaries (power steering,
power-assisted brakes, air conditioning, on-board systems) via a
generator mounted on the V12 engine when running 100 per cent under
electric drive. It also incorporates the hybrid systems cooling
pump.This experimental vehicle thus maintains the high-performance
characteristics typical of all Ferraris while, at the same time,
reducing CO2 emissions on the ECE + EUDC combined cycle by 35 per
cent.
6.3. VolvoVolvo is experimenting with a Formula 1 style drive
system which is claimed to cut fuel consumption by up to 20 per
cent. The Swedish car maker is about to start road trials using a
vehicle fitted with a kinetic energy recovery system, or KERS.
Volvo is using the technology not only to improve performance but
also to aid fuel economy.It uses a flywheel fitted to the rear axle
which captures energy from the car under braking. The flywheel
spins at up to 60,000rpm and when the car moves away the stored
energy is released to drive the rear wheels via a special
transmission. Volvo says that when allied to stop/start systems
which switch off a car's engine when it comes to rest in traffic,
the Flywheel KERS reduces fuel urban fuel consumption by some 20
per cent.Volvo aims to develop a complete system for kinetic energy
recovery. Tests in a Volvo car will get under way in the second
half of 2011. This technology has the potential for reducing fuel
consumption by up to 20 per cent. What is more, it gives the driver
an extra horsepower boost, giving a four - cylinder engine
acceleration like a six-cylinder unit. They claim that the system
can have the effect of adding an extra 80 horsepower to an engine
which could significantly improve acceleration.They are not the
first manufacturer to test flywheel technology, but nobody else has
applied it to the rear axle of a car fitted with a combustion
engine driving the front wheels. The Swedish carmaker expects cars
with flywheel technology to reach the showrooms within a few years
if the tests and technical development go as planned.
Fig 5.3. Volvo Flywheel KERS System Layout
6.4. JaguarA consortium led by a Jaguar Land Rover is developing
a flywheel-hybrid system that it says boosts performance by 60
kilowatts (about 80 horsepower) while improving fuel efficiency 20
percent. The consortium, which includes automakers like Ford and
engineering firms like Prodrive, sees a market for flywheel hybrids
among luxury automakers.During braking, a small continuously
variable transmission (CVT) mounted on the rear differential
transfers the kinetic energy to a flywheel. When the driver applies
the accelerator, the flywheel returns the energy through the CVT to
the wheels, providing a boost of 60 kilowatts for around 7 seconds.
The flywheel spins at up to 60,000 rpm.Jaguar is testing its purely
mechanical flywheel system, which reportedly weighs 143 pounds, in
an XF sedan. Jaguar says it is superior to battery-electric hybrid
systems because flywheels are smaller, cheaper and more efficient.
Instead of converting kinetic energy into electricity that is
stored in a battery, the CVT transfers the energy directly to the
flywheel and then back to the wheels.
7. CONCLUSIONBy adopting the cheaper and lighter flywheel system
(the ideal solution if it could be made to fit into the
no-refueling era cars), a more powerful boost, and limiting the
number of activations in a raceit would cover all the bases it
needs to. It would be affordable for the all the teams, deliver
performances as well as being a more interesting race variable. The
sidepod solution is quite unique, and has given us a new envelope
to try to drive performance to the rear of the car. We need to keep
thinking out-of-the-box. Compared to ten or 20 years ago, it's
really quite staggering what can be delivered given the
restrictions we have now it's a tribute to imaginative thinking
Thus we are coming to the end of the elaborate study of KERS
going through their advantaged limitation relevance and finally to
the modification. To sum up this seminar we have gone through
sophisticated concept which will surely be much raved in coming
days.Also it would be a great showcase of technology which could
have a major impact on the car industry in years to come. In the
future the technology could also be used on buses, trains, and wind
power generation.
8. REFERENCE
1. www.howstuffworks.com/KERS.htm
2. www.wikipedia.org/wiki/Kinetic_Energy_Recovery_Systems
3. www.flybridsystems.com/F1System.html
4. www.ferrari.com/KERS/HY-KERS-Experimental-Vehicle.aspx
5. www.scarbsf1.wordpress.com/2010/10/20/kers-anatomy
6.
www.wired.com/autopia/2010/10/flywheel-hybrid-system-for-premium-vehicles
7. www.gizmag.com/mechanical-kers-technology-for-road-cars
www.final-yearproject.com | www.finalyearthesis.com1 ASIET,
KaladyDept. of Mechanical Engineering