Chapter 1
INTRODUCTION
1.1 Heat Engines
A heat engine is a device, which transfers the chemical energy of a fuel into thermal energy and uses this energy to produce the mechanical work.
Heat engines are classified as,
1. External Combustion Engines.
2. Internal Combustion Engines. External combustion engine is one in which the products of combustion of air and fuel transfer heat to a second fluid, which then becomes the functional fluid for producing power. Steam engine is an example of E C Engine.
The product output of combustion of air and fuel becomes precisely the working fluid in Internal Combustion Engine. Diesel engine, jet engine, Petrol engines, the open cycle gas turbine, gas engine are the examples of I C Engines.
Internal combustion engines are
…show more content…
Air intake into the engine cylinder is not throttled; the total amount of fuel injected or supplied per cycle regulates the engine torque and power.
Considering the entering air is not throttled, pressure in the intake manifold is typically at an equivalent close to one atmospheric pressure. This makes the indicator diagram of the engine cycle is very small, with a comparable better thermal efficiency than SI engine. This is exceptionally perfect at low speeds and less loads. For CI engines,
Wnet = Wgross - Wpump
Only atmospheric air is confined in the engine cylinder throughout the compression stroke, and higher compression ratios are operated in Compression Ignition engines. Compression ratios of modern day Compression Ignition engines are differs from 12 to 24. After all, because the comprehensive air-fuel ratio on which Compression Ignition engines work is quite lean (equivalence ratio cp = 0.8), reduced brake power output is frequently obtained for a provided engine
This paper has informed you on multiple parts and operations of 7.3 litre injectors. Listing their parts, both internal and external. How the entire system works as one, and how it makes the engine run. Without fuel of some sort the engine would not run. So with this research paper I hope you have learned something.
Cummins has a history of innovation beginning in 1919 when it was founded and produced its first diesel engine, a 1.5 to 8 horsepower model used to power pumps. In 1929, a Cummins engine powered the first diesel-powered U.S car. The company continued to advance in the diesel engine and power generation industry, and in 1958 Cummins Filtration was started to meet the high-performance requirements of Cummins diesel engines (Cummins Inc.). In 1985, Cummins introduced aerodynamic contours to Class 8 trucks years ahead of its time. This new shape greatly reduced air flow drag and, combined with a lightweight engine, attained up to 20 percent higher fuel efficiency than similar vehicles at the time. In 1999, Beijing Public Transit launched a fleet of 300 buses with Cummins B5.9 engines to improve city air quality, being the first clean, alternative fuel fleet in Asia and remains the largest in the world, with more than 3500 Cummins Westport natural gas powered buses (Cummins Inc.). These are just a few examples demonstrating a history marked by improvement and innovation of new technologies in order to reduce emissions and increase efficiencies for the benefit of the environment.
...ese dangerously harmful gasses would be released into our atmosphere by all combustion engines. Although the catalytic converter when operating at its optimal temperature can break down over 95% percent of the harmful gasses produced by the engine it does not do a well at all when not at high temperatures. It takes about five miles of driving for most vehicles to reach a temperature at which the reactions will reach near completion, before this temperature the catalytic converter does practically nothing to convert these harmful gases. Some catalytic converters now have coils running from the engine to the catalytic converter to heat the catalytic converter to its optimal temperature soon after the engine has started to produce harmful gasses. With this improvement the catalytic converter can effectively reduce almost all of the carbon monoxide and nitrogen oxide.
The diesel engines combustion process is a little different than the typical gasoline engine. A couple main things that diesel engines have that gasoline engines do not are, carburetors and spark plugs. Unlike a gasoline engine, air is first allowed into the cylinder rather than a fuel and air mixture. Once the air is compressed it creates a source of heat, then a mist of fuel is injected to start the combustion process which then creates the energy. Since diesel engines do not have spark plugs they are able to take in larger amount of fuel, this obviously means there will be more power and will guarantee better efficiency. Another thing that is very important is that diesel tends to be a better lubricant than gasoline, being that it is a better lubricant there will be less friction which will generally increase the life of the engine (Woodford). Diesel engines operate at slower speeds than gasoline engines, therefore diesel engines tend to have longer lifespans than gasoline
One type of engine is a called a fuel cell. A fuel cell operates like a battery. Unlike a battery, a fuel cell does not run down or require recharging. It will produce energy in the form of electricity and heat as long as fuel is supplied. A fuel cell consists of two electrodes sandwiched around and electrolyte. Oxygen passes over one electrode and hydrogen over the other, generating electricity, water and heat. Hydrogen fuel is used to make all this work. Fuel cell emissions are nothing but water vapor.
3.Combustion: As the piston reaches the top of its stroke or TDC, the spark plug fires, igniting the mixture. Due to the high compression of this mixture it is very volatile and it explodes when the spark is introduced. This pushes the piston downward and produces power.
Starting from the point where the spark plug fires. Previous to this, the piston has compressed the fuel/air mixture in the cylinder. When the spark plug fires, it creates an explosion. This explosion drives the piston downward which turns the crankshaft, which is attached to the shaft that drives the cutting deck on the lawn mower. As this is happening it is compressing the fuel/air mixture that has come from the carburetor, in the crank case. As the piston starts to go down, the exhaust port is uncovered, and the pressure in the cylinder forces most of the exhaust gases out of the chamber.
The jet engine is a great mechanical piece of engineering. It has been used in almost all aircraft since its invention. This one improvement in aircraft allowed aircraft to fly higher, faster, and more efficient. The turbocharged engine invented by GE was the main building block for other engines. Since its invention, the jet engine has been the workhorse for all jet powered aircraft.
...al combustion vehicle emissions. Sustainable practices, technology, collaborations are producing a new breed of vehicles aiming for a greener future for the world. These efficient vehicles seek to forge a green future.
Diesel engines are a marvel of the world and have been since creation in 1892. Today there are several types of these engines including, two-stroke and four-stroke engines as well as the idea of how diesel engines operate. The diesel engine is a necessary component of the shipping industry as well as the daily lives of people.
Heat energy is transferred through three ways- conduction, convection and radiation. All three are able to transfer heat from one place to another based off of different principles however, are all three are connected by the physics of heat. Let’s start with heat- what exactly is heat? We can understand heat by knowing that “heat is a thermal energy that flows from the warmer areas to the cooler areas, and the thermal energy is the total of all kinetic energies within a given system.” (Soffar, 2015) Now, we can explore the means to which heat is transferred and how each of them occurs. Heat is transferred through conduction at the molecular level and in simple terms, the transfers occurs through physical contact. In conduction, “the substance
The invention of internal combustion engines in the early 19th century has led to the discovery of utilisation of cheap energy that is petroleum and this enabled the world to develop and progress into the modern world today. Humans were able to accomplish more work done with little manual labour, using internal combustion engines powered by fossil fuels. Internal combustion engine are mechanical power devices that convert heat energy to mechanical energy with the combustion process taking place in a system boundary (Rolle, 2005). Among the internal combustion engine invented in the 19th century were the Otto engine, Diesel engine and gas turbine engine. Gas turbine engine is one of the popular engines used today due to its high torque per weight ratio relative to other types of internal combustion engines. As explained by Cengel and Boles (2011), the gas turbine engine works on a 6 stages process, namely air intake, compression, fuel injection, combustion, expansion and exhaust (refer to Figure 1 in Appendix 1).
A steam turbine's two main parts are the cylinder and the rotor. As the steam passes through the fixed blades or nozzles it expands and its velocity increases. The high-velocity jet of steam strikes the first set of moving blades. The kinetic energy of the steam changes into mechanical energy, causing the shaft to rotate. The steam then enters the next set of fixed blades and strikes the next row of moving blades. As the steam flows through the turbine, its pressure and temperature decreases, while its volume increases. The decrease in pressure and temperature occurs as the steam transmits energy to the shaft and performs work. After passing through the last turbine stage, the steam exhausts into the condenser or process steam system. The kinetic energy of the steam changes into mechanical erringly through the impact (impulse) or reaction of the steam against the blades.
Now, what are electric vehicles really? Simply put, electric vehicles are vehicles that are powered by an electric motor instead of an internal combustion engine. Electric vehicles use electricity as the “fuel” instead of gasoline or some other combustible fuel. The electric motor in an electric vehicle converts electricity, usually from a battery pack, into mechanical power to turn the wheels. Major auto manufacturers are producing high-performance electric vehicles not only in the form of cars but also in a wide range of styles and sizes, including, mini-vans, sport utility vehicles and pickup trucks.
In my undergraduate years, I have acquired a strong background in the fundamentals of basic mechanical engineering, having studied subjects such as Strength of Materials, Thermodynamics, Fluid Mechanics, Heat and Mass Transfer, Design of Machine Elements and Automobile Engineering. Whilst pursuing my diploma & degree courses, my interest for Automotive Engineering grew even more having learnt more on the different types of internal combustion engines, their configuration and importance. However, what I lacked was a practical understanding on these core areas of Automotive Engineering. To gain a better understandi...