AMG 5.5-liter M 157 Biturbo Crank Assembly
1.1 Introduction and Historical Perspective
1.2 Engine Classifications
1.3 Engine Operating Cycles
1.4 Engine Components
1.5 Spark-Ignition Engine Operation
1.6 Examples of Spark-Ignition Engines
1.7 Compression-Ignition Engine Operation
1.8 Examples of Diesel Engines
1.9 Stratified-Charge Engines
1.1 Introduction and Historical Perspective
Two other technological occurrences stimulated the emergence of the internal combustion
engine.
Refinery
In 1859, the discovery of crude oil finally made available the development of the reliable fuels
which could be used in these newly developed engines.
World War II was the apex of the V12 engine, we can know the German Tiger Tank,
Soviet T-34, America P-51 Mustang used the V12 engine as the propulsion, in the modern
automotive industry, High end sports car, such as Ferrari, Lamborghini, Aston Martin DB9...
eMercedesBenz Feature: The World's First Production Car, The Benz Patent Motor Car Velocipede Of 1894
Karl Benz played a prominent role in promoting the development of the automobile. Some 25 units of the Benz Patent Motor Car of 1886 – the world's first automobile – were built. It goes without saying that Benz knew that a four-wheeled car would have greater cornering stability, however, he found the steering systems used for carriages at the time to be unsuitable for his purposes. He solved the problem – and filed a patent for his double-pivot steering (DRP 73515) in 1893. He installed it in the same year in his four-wheeled Victoria model. However, he had a lighter car in mind. At the World Exposition in Chicago (May 1 – October 31, 1893), Benz finally presented his Velocipede to the public. It was to become the world's first car from large-scale production and at the same time the first small car. Benz produced more than 1,200 units of this car between 1894 and 1902.
The Benz Velo of 1894 was the world's first large-scale production car.
At the beginning of the 20th century the automobile was a plaything for the rich. Most models were complicated machines that required a chauffer conversant with its individual mechanical nuances to drive it. Henry Ford was determined to build a simple, reliable and affordable car; a car the average American worker could afford. Out of this determination came the Model T and the assembly line - two innovations that revolutionized American society and molded the world we live in today.
Ford Model T
1.2 Engine Classifications
1. Types of Ignition
(a) Spark Ignition
(b) Compression Ignition
When the air-fuel mixture self-ignites due to high temperature in the combustion chamber
caused by high compression.
HCCI (or Homogenous Charge Compression Ignition) engine, GM's experimental powerplant works on a phenomenon which normally spells mechanical doom for conventional petrol motors.
2. Engine Cycles
(a) four-stroke
(b) two-stroke
A two-stroke cycle has two pistons movement over one revolution for each cycle.
3. Valve Location
4. Basic Design
5. Piston and Number of Cylinders of Reciprocating Engines
(a) Single Cylinder
(b) In-Line
(c) V-Engine
Two banks of cylinders at an angle of each other along a single crankshaft.
(d) Opposed Cylinder Engine
(e) W Engine.
Same as the V engine except with three banks of cylinders on the same crankshaft.
(f) Opposed Piston Engine
Two pistons in each cylinder with the combustion chamber in the center between the
cylinders.
(g) Radial Engine
Engine with pistons positioned in a circular plane around the central crankshaft.
6. Air Intake Process
(a) Naturally Aspirated.
No intake air pressure boost system.
2008 Dodge Viper 8.4-liter V10. Naturally Aspirated.
(b) Supercharged.
Intake air pressure increased with the compressor driven by the engine crankshaft.
Chevrolet Camaro Supercharged.
(c) Turbocharged.
Intake air pressure increased with the turbine-compressor driven by the engine exhaust
gases.
(d) Crankcase Compressed.
7. Fuel Input for Spark Ignition Engine
(a) Carburetor.
(b) Multi-point Port Fuel Injection.
(c) Throttle Body Fuel Injection.
8. Fuel Used
9. Application
10. Types of Cooling
(a) Air Cooled
(b) Liquid Cooled.
1.3 Engine Operating Cycles
....
1.4 Engine Components
Poppet Valve.
(A) Valve Seat
(B) Head
(C) Stem
(D) Guide
(E) Spring
(F) Camshaft
(G) Manifold
Push Rods :
Mechanical linkage between the camshaft and valves on overhead valve engines with the
camshaft in the crankcase.
Twin turbocharger :The turbine casing is welded to the exhaust manifold.
Valve assembly : The continuous adjustment of the intake and exhaust camshafts occurs
depending on load and engine speed.
Variable : The fuel pressure in the high pressure rail is regulated between 100 ~ 200 bar.
1-6 Basic Engine Cycle
Four Stroke Spark Ignition Engine
1. (1 Stroke) Intake Stoke and Induction
The piston travels from TDC to BDC with the intake valve open and exhaust closed.
This creates an increasing volume in the combustion chamber, which in turn it creates
a vacuum (This process is like using the syringe to suck air). The resulting pressure differential
through the intake system from atmospheric pressure on the outside to the vacuum on the
inside causes air to be pushed into the cylinder. As the air passes through the intake system,
fuel is added to it in the desired amount by means of fuel injectors or a carburetor.
2. (2 Stroke) Compression Stroke
When the piston reaches the BDC, the intake valve closes and the piston travels back to TDC
with all valves closed. This compresses the air-fuel mixture, rising both the pressure and
temperature in the cylinder. Near the end of the compression stroke, the spark plug is ignited
and combustion is initiated.
3. Combustion
Combustion of the air-fuel mixture occurs in a very short but finite length time with the piston
near TDC (nearly constant-volume combustion)
4. (3 Stroke) Expansion Stroke or Power Stroke
With all valves closed, the high pressure created by the combustion process pushes the
piston away from TDC. This is the stroke which produces the work output of the engine cycle.
5. Exhaust Blowndown
late in the power stroke, the exhaust valve is opened and exhaust blowndown occurs.
Pressure and temperature in the cylinder are still high relative to the surroundings at this point,
and a pressure differential is created though the exhaust system which is open to atmospheric
pressure.
6. (4 Stroke) Exhaust Stroke
By the time the piston reaches BDC, exhaust blowndown is complete, but the cylinder is still
full of exhaust gases at approximately atmospheric pressure. When the exhaust valve
remaining open, the piston now travels from BDC to TDC in the exhaust valve. This pushes
most of remaining exhaust gases out of the cylinder into the exhaust system at about
atmospheric pressure.
Near the end of the exhaust stroke bTDC, the intake valve starts to open, so that it is fully
open by TDC when the new intake stroke starts the next cycle. Near TDc the exhaust valve
start to close and finally is fully closed sometime aTDC. This period when both the intake valve
and exhaust valve are open is called Valve Overlap (due to air has inertial).
- (a)Intake Stroke. Ingress air-fuel as the piston moves from TDC to BDC.
- (b)Compression Stroke. Piston moves from BDC to TDC. Spark ignition occurs near the end of compression stroke.
- (c)Combustion at almost constant-volume near TDC.
- (d)Power or expansion stroke. High cylinder pressure pushes the piston from TDC to BDC.
- (e)Exhaust Blowndown when exhaust valve opens near end of expansion stroke.
- (f)Exhaust stoke.
Four Stroke Compression Ignition Engine
Two Stroke Spark Ignition (SI) Engine
Two Stroke Compression Ignition (CI) Engine
The two stroke cycle for a compression engine is similar to that of the SI engine except for
two changes. No fuel is added to the incoming air, so that compression is done on air only.
Instead of a spark plug, a fuel injector is located in the cylinder. Near the end of the compression stroke, fuel is injected into the hot compressed air and combustion is initiated
by self-ignition.
Two stroke compression ignition engine.
7. Engine Emissions and Air Pollution
Four major emissions produced by internal combustion engine are hydrocarbon (He),
carbons monoxide (CO), oxides of nitrogen (NOx) and solid particles.
Kent Shockley - Driver
Hydrocarbons are fuel molecules which did not get burned and smaller nonequilibrium
particles of partially burned fuel. Carbon monoxide occurs when not enough oxygen is presented to fully react all carbon to carbon dioxides or when incomplete air-fuel mixture occurs when due to the very short engine cycle time. Oxide of nitrogen are created in an engine when high combustion temperatures ...
No comments:
Post a Comment