An Otto cycle

An Otto cycle is an idealized thermodynamic cycle which
describes the functioning of a typical spark ignition
reciprocating piston engine, the thermodynamic cycle most
commonly found in automobile engines.
The processes are described by
Process 1-2 is an isentropic compression of the air as the
piston moves from bottom dead centre (BDC) to top dead
centre (TDC).
Process 2-3 is a constant-volume heat transfer to the air
from an external source while the piston is at top dead
centre. This process is intended to represent the ignition of
the fuel-air mixture and the subsequent rapid burning.
Process 3-4 is an isentropic expansion (power stroke).
Process 4-1 completes the cycle by a constant-volume
process in which heat is rejected from the air while the
piston is a bottom dead centre.y

Pump Assembly

Pump Assembly ##
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A fuel pump is a frequently (but not always) essential
component on a car or other internal combustion engined
device. Many engines (older motorcycle engines in
particular) do not require any fuel pump at all, requiring only
gravity to feed fuel from the fuel tank through a line or hose
to the engine. But in non-gravity feed designs, fuel has to be
pumped from the fuel tank to the engine and delivered under
low pressure to the carburetor or under high pressure to the
fuel injection system.

Herringbone gears

What are Herringbone gears and what for these are used ?
In normal helical gears there is no problem of impact
stresses but there are axial thrusts on the bearings of shafts
on which they are mounted.these gears are good for
moderate power transmission because bearing can be
designed.But in very high power transmission design of
bearing for a small and compact system becomes very tough
and unemployable.Thus herringbone gears were designed to
eliminate these axial thrusts.This gear contains both right
hand helical profile and left hand helical profile on same gear
as you can see in diagram.The axial components of
transmission force is cancelled by each other on same
gear.Thus eliminating the problem of thrust force.
These gears are used in racing cars where high power
transmission is required and bearing size can not be
increased after certain limit.

Volkswagen Aqua

Volkswagen Aqua:
Chinese designer creates eco-friendly all-terrain car for land,
water and ice.
Created by Chinese designer Yuhan Zhang, the Volkswagen
Aqua would be powered by a hydrogen fuel cell and would
emit zero carbon dioxide.The all-terrain vehicle, which has a
top speed of 62mph and works like a hovercraft, can move
seamlessly between different surfaces.

PURPOSE AND FUNCTION OF A CLUTCH

PURPOSE AND FUNCTION OF A CLUTCH
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The clutch assembly is located between the engine and the
transmission/transaxle. The purpose and function of a clutch
include the following:
1-To disconnect the engine from the transmission/transaxle
to permit the engine to remain running when the vehicle is
stopped and to permit the transmission/transaxle to be
shifted
Connect and transmit engine torque to the transmission/
transaxle
2-To dampen and absorb engine impulses and drivetrain
vibration
3-To provide a smooth engagement and disengagement
between the engine and the transmission/transaxle.

POWER STEERING

POWER STEERING:
Power steering assists the driver of an automobile in
steering by directing a portion of the vehicle’s power to
traverse the axis of one or more of the road wheels. As
vehicles have become heavier and switched to front wheel
drive, particularly using negative offset geometry, along with
increases in tire width and diameter, the effort needed to
turn the steering wheel manually has increased often to the
point where major physical exertion is required. To alleviate
this, auto makers have developed power steering systems:
or more correctly power-assisted steering on road going
vehicles there has to be a mechanical linkage as a fail safe.
There are two types of power steering systems hydraulic
and electric/electronic.

Newcomen Atmospheric Engine

Newcomen Atmospheric Engine ##
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The atmospheric engine invented by Thomas Newcomen in
1712, often referred to simply as a Newcomen engine, was
the first practical device to harness the power of steam to
produce mechanical work.Newcomen engines were used
throughout Britain and Europe, principally to pump water out
of mines, starting in the early 18th century. James Watt's
later Watt steam engine was an improved version of the
Newcomen engine. As a result, Watt is today better known
than Newcomen in relation to the origin of the steam engine.

SCUDERI ENGINE

SCUDERI ENGINE:
The basic concept of the Scuderi Engine is to divide the four
strokes of a standard engine over a paired combination of
one compression cylinder and one power (or expansion)
cylinder.
CONCEPT OF DESIGN:
Gas is compressed in the compression cylinder and
transferred to the power cylinder through a gas passage.
The Scuderi Split-Cycle Engine changes the heart of the
conventional engine by dividing (or splitting) the four strokes
of the Otto cycle over a paired combination of one
compression cylinder and one power cylinder.
IMPACT OF TECHNOLOGY:
Fuel efficiency improvements of 15% - 30% initially with
further improvements possible.
Potential reduction of NOx emissions of 50% - 80%.
Lower average operating engine speed reduces engine wear
and tear.
Design Flexibility-more controllable parameters available for
achieving enhanced or customized performance.

Magneto ignition system

Magneto ignition system
An ignition magneto is a magneto that provides current for
the ignition system of a spark-ignition engine, such as a
petrol engine. It produces pulses of high voltage for the spark
plugs.The use of ignition magnetos is now confined mainly
to engines where there is no other available electrical supply,
for example in lawnmowers and chainsaws. It is also widely
used in aviation piston engines even though an electrical
supply is usually available. This is because a magneto
ignition system is more reliable than a battery-coil system.
People discussing magnetos and coils used in early internal-
combustion engines generally used the term "tension"
instead of the more modern term "voltage."

Wankel engine

Wankel engine:-
The Wankel engine is a type of internal combustion engine
using an eccentric rotary design to convert pressure into a
rotating motion instead of using reciprocating pistons. Its
four-stroke cycle takes place in a space between the
inside of an oval-like epitrochoid-shaped housing and a
rotor that is similar in shape to a Reuleaux triangle but
with sides that are somewhat flatter. The very compact
Wankel engine delivers smooth high-rpm power. It is
commonly called a rotary engine, though this name applies
also to other completely different designs.
Due to their compact design, Wankel rotary engines have
been installed in a variety of vehicles and devices including
automobiles, motorcycles, racers, aircraft, go-karts, jet
skis, snowmobiles, chain saws, and auxiliary power units.

Disc brakes

Disc brakes
Disc brakes are an order of magnitude better at stopping
vehicles than drum brakes, which is why you'll find disc
brakes on the front of almost every car and motorbike built
today. Sportier vehicles with higher speeds need better
brakes to slow them down, so you'll likely see disc brakes on
the rear of those too.
Disc brakes are again a two-part system. Instead of the
drum, you have a disc or rotor, and instead of the brake
shoes, you now have brake caliper assemblies. The caliper
assemblies contain one or more hydraulic pistons which
push against the back of the brake pads, clamping them
together around the spinning rotor. The harder they clamp
together, the more friction is generated, which means more
heat, which means more kinetic energy transfer, which slows
you down. You get the idea by now.

Surface Condenser

Surface Condenser ##
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A surface condenser is a commonly used term for a water-
cooled shell and tube heat exchanger installed on the
exhaust steam from a steam turbine in thermal power
stations. These condensers are heat exchangers which
convert steam from its gaseous to its liquid state at a
pressure below atmospheric pressure. Where cooling water
is in short supply, an air-cooled condenser is often used. An
air-cooled condenser is significantly more expensive and
cannot achieve as low a steam turbine exhaust pressure as
a water-cooled surface condenser.

Liquid Rocket Engine

Liquid Rocket Engine ##
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A liquid-propellant rocket or a liquid rocket is a rocket
engine that uses propellants in liquid form. Liquids are
desirable because their reasonably high density allows the
volume of the propellant tanks to be relatively low, and it is
possible to use lightweight centrifugal turbopumps to pump
the propellant from the tanks into the combustion chamber,
which means that the propellants can be kept under low
pressure. This permits the use of low-mass propellant tanks,
resulting in a high mass ratio for the rocket.
An inert gas stored in a tank at a high pressure is
sometimes used instead of pumps in simpler small engines
to force the propellants into the combustion chamber. These
engines may have a lower mass ratio, but are usually more
reliable 186,187 and are therefore used widely in satellites
for orbit maintenance.

4 stroke IC engine

The internal combustion engine is an engine in which the
combustion of a fuel (normally a fossil fuel ) occurs with an
oxidizer (usually air) in a combustion chamber that is an
integral part of the working fluid flow circuit. In an internal
combustion engine (ICE) the expansion of the high-
temperature and high- pressure gases produced by
combustion apply direct force to some component of the
engine. The force is applied typically to pistons, turbine
blades, or a nozzle. This force moves the component over
a distance, transforming chemical energy into useful
mechanical energy . The first commercially successful
internal combustion engine was created by Étienne Lenoir .
[1]
The term internal combustion engine usually refers to an
engine in which combustion is intermittent, such as the
more familiar four-stroke and two-stroke piston engines,
along with variants, such as the six-stroke piston engine
and the Wankel rotary engine. A second class of internal
combustion engines use continuous combustion: gas
turbines , jet engines and most rocket engines, each of
which are internal combustion engines on the same
principle as previously described.[1]
The ICE is quite different from external combustion
engines, such as steam or Stirling engines , in which the
energy is delivered to a working fluid not consisting of,
mixed with, or contaminated by combustion products.
Working fluids can be air, hot water, pressurized water or
even liquid sodium, heated in some kind of boiler . ICEs are
usually powered by energy-dense fuels such as gasoline or
diesel, liquids derived from fossil fuels . While there are
many stationary applications, most ICEs are used in mobile
applications and are the dominant power supply for cars,
aircraft, and boats.
A four-stroke engine (also known as four-cycle ) is an
internal combustion engine in which the piston completes
four separate strokes which comprise a single
thermodynamic cycle. A stroke refers to the full travel of
the piston along the cylinder, in either direction. While
risqué slang among some automotive enthusiasts names
these respectively the "suck," "squeeze," "bang" and "blow"
strokes. [1] they are more commonly termed
1. INTAKE: this stroke of the piston begins at top dead
center. The piston descends from the top of the
cylinder to the bottom of the cylinder, increasing the
volume of the cylinder. A mixture of fuel and air is
forced by atmospheric (or greater) pressure into the
cylinder through the intake port.
2. COMPRESSION: with both intake and exhaust valves
closed, the piston returns to the top of the cylinder
compressing the air or fuel-air mixture into the
cylinder head.
3. POWER: this is the start of the second revolution of
the cycle. While the piston is close to Top Dead
Centre, the compressed air–fuel mixture in a
gasoline engine is ignited, by a spark plug in gasoline
engines, or which ignites due to the heat generated
by compression in a diesel engine. The resulting
pressure from the combustion of the compressed
fuel-air mixture forces the piston back down toward
bottom dead centre.
4. EXHAUST: during the exhaust stroke, the piston once
again returns to top dead centre while the exhaust
valve is open. This action expels the spent fuel-air
mixture through the exhaust valve(s).

Diesel Engine Technical details:

Diesel Engine Technical details:
The design of Diesel engine is mostly alike the one of the
petrol engine – both have pistons, cylinders, valves. But the
ignition system in Diesel engines is lack in principle. Instead
of the usual spark in Diesel engines the fuel-air mixture is
ignited by high temperature of the compressed air. Let’s
review the Diesel engine operating principle.
The Diesel engine operating scheme
1-th stroke. The piston is moving down till lower dead point
and the fresh air is blown from intake valve.
2-th stroke. The piston is moving up till upper dead point
and the air in the cylinder is compressed multiple times (14
up to 25) and its temperature raises up to 700-800 C.
3-th stroke. At the moment the pistol reaches the upper
dead point the fuel is injected into cylinder. Combustion act.
The fuel-air mixture is expands and the piston is going
down.
4-th stroke. The piston is going down, and gases are
exhausted throw the open exhaust valve.
The fuel in the cylinder ignites with rapid pressure jump that
makes the engine to work noisy and with vibration. To
preserve the operation safety on the required level the Diesel
engine is designed much more durable than the petrol
engine. More durability assumes more heavy-weighted.
The fuel supply system of Diesel engine also differs from the
petrol-powered engine. The first thing to say it is more
complicated. The fuel in the combustion chamber should be
injected under high pressure and it is very minor in volume.
The engine is controlled by the electronic unit, which
controls the fuel pump and the injector according to data get
from sensors. That kind of design makes the engine much
more expensive.

Multimode manual transmission (MMT )

Multimode manual transmission (MMT )
........................................................
Multimode Manual Transmission (MMT or M/M, also
Multimode Transmission) is a type of sequential manual
transmission offered by Toyota. It uses a traditional manual
gearbox with an electronically controlled clutch. Multimode
Manual Transmission is available in the Aygo, Yaris, Corolla,
Corolla Verso and Auris in Europe, and should not be
confused with Multimode Automatic Transmission, which is
offered in the North American market by Toyota.
The Multimode Manual Transmission has the following gears:
R, N, E, M+, M-.
•R: R is the reverse gear. It is similar to R in both traditional
manual and in full automatic cars.
•N: N is the neutral gear. It is similar to N in both traditional
manual and full automatic.
•E: E is the functional equivalent of D in a full automatic. As
the gearbox in a MMT car is a manual gearbox, instead of
one with a torque converter as in a traditional automatic,
gear changes are noticeable. The accelerator should be
eased off slightly when gear changes to produce a smooth
ride.
•M- : Downshifts a gear in sequential fashion, from M5 (M6
in 6-speed MMT cars) to M1.
•M+: Up-shifts a gear in sequential fas

IC Engine Cooling System By Air Cooling Method

IC Engine Cooling System By Air Cooling Method ##
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Heat engines generate mechanical power by extracting
energy from heat flows, much as a water wheel extracts
mechanical power from a flow of mass falling through a
distance. Engines are inefficient, so more heat energy enters
the engine than comes out as mechanical power; the
difference is waste heat which must be removed. Internal
combustion engines remove waste heat through cool intake
air, hot exhaust gases, and explicit engine cooling.Engines
with higher efficiency have more energy leave as mechanical
motion and less as waste heat. Some waste heat is
essential: it guides heat through the engine, much as a water
wheel works only if there is some exit velocity (energy) in
the waste water to carry it away and make room for more
water. Thus, all heat engines need cooling to operate.

Piston

A piston is a component of reciprocating engines ,
reciprocating pumps, gas compressors and pneumatic
cylinders, among other similar mechanisms. It is the
moving component that is contained by a cylinder and is
made gas-tight by piston rings. In an engine, its purpose is
to transfer force from expanding gas in the cylinder to the
crankshaft via a piston rod and/or connecting rod . In a
pump, the function is reversed and force is transferred from
the crankshaft to the piston for the purpose of
compressing or ejecting the fluid in the cylinder. In some
engines, the piston also acts as a valve by covering and
uncovering ports in the cylinder wall.
Piston engines
Main article: Reciprocating engine
Internal combustion engines
Internal combustion engine piston, sectioned to show the
gudgeon pin.
The piston of an internal combustion engine is acted upon
by the pressure of the expanding combustion gases in the
combustion chamber space at the top of the cylinder. This
force then acts downwards through the connecting rod and
onto the crankshaft . The connecting rod is attached to the
piston by a swivelling gudgeon pin (US: wrist pin). This pin
is mounted within the piston: unlike the steam engine,
there is no piston rod or crosshead (except big two stroke
engines).
The pin itself is of hardened steel and is fixed in the
piston, but free to move in the connecting rod. A few
designs use a 'fully floating' design that is loose in both
components. All pins must be prevented from moving
sideways and the ends of the pin digging into the cylinder
wall, usually by circlips .
Gas sealing is achieved by the use of piston rings. These
are a number of narrow iron rings, fitted loosely into
grooves in the piston, just below the crown. The rings are
split at a point in the rim, allowing them to press against
the cylinder with a light spring pressure. Two types of ring
are used: the upper rings have solid faces and provide gas
sealing; lower rings have narrow edges and a U-shaped
profile, to act as oil scrapers. There are many proprietary
and detail design features associated with piston rings.
Pistons are cast from aluminium alloys . For better
strength and fatigue life, some racing pistons may be
forged instead. Early pistons were of cast iron , but there
were obvious benefits for engine balancing if a lighter alloy
could be used. To produce pistons that could survive
engine combustion temperatures, it was necessary to
develop new alloys such as Y alloy and Hiduminium ,
specifically for use as pistons.
A few early gas engines [note 1] had double-acting
cylinders, but otherwise effectively all internal combustion
engine pistons are single-acting . During World War II, the
US submarine Pompano[note 2] was fitted with a prototype
of the infamously unreliable H.O.R. double-acting two-
stroke diesel engine. Although compact, for use in a
cramped submarine, this design of engine was not
repeated.

CRAWLER DOZER KOMASTU

## CRAWLER DOZER KOMASTU ##
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The Komatsu D575A is a 1,150 horsepower (860 kW) tractor
crawler available as a bulldozer/ripper, the D575A-3, or as a
dedicated bulldozer, the D575A-3 SD Super Dozer.Equipped
with a standard blade, both versions are capable of moving
90 cubic yards (69 m3) of material per pass although the
D575A-3 SD Super Dozer is capable of moving 125 cubic
yards (96 m3) of material per pass if equipped with an
optional blade.The D575A-3 can dig to a maximum depth of
6 feet 9 inches (2.06 m) using its single shank ripper.

An indexing head

An indexing head:-
also known as a dividing head or spiral head,is a specialized
tool that allows a workpiece to be circularly indexed; that is,
easily and precisely rotated to preset angles or circular
divisions.
Indexing heads are usually used on the tables of milling
machines, but may be used on many other machine tools
including drill presses, grinders, and boring machines.
Common jobs for a dividing head include machining the
flutes of a milling cutter, cutting the teeth of a gear, milling
curved slots, or drilling a bolt hole circle around the
circumference of a part.