Most small vehicles, such as cars and pickup trucks, use gasoline as fuel. Large vehicles such as buses, delivery trucks, and long-haul tractor trailers typically run on diesel.
Gasoline and diesel engines have different strengths, so both fuel types are required. as me automotive engineering student This makes it suitable for a variety of uses.
Let’s start with what they have in common. Both gasoline and diesel engines operate through a process called . internal combustion engine.
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First, the fuel and air are mixed together because oxygen in the air is required for the fuel to burn.
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The fuel and air mixture is then compressed and the mixture becomes hot enough to burn.
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The engine then burns the mixture of fuel and air, releasing heat. This creates high pressure, which moves internal parts and causes the car to move.
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Finally, cars release spent combustion gases into the atmosphere through their tailpipes. These gases Contains pollutantscarbon monoxide, nitrogen oxides, unburned fuel, etc. harmful to human healthas well as carbon dioxide, which warms the Earth’s atmosphere.
How a gas-powered internal combustion engine converts the chemical energy in gasoline into the kinetic energy that powers the car.
Different engines for different jobs
Both gasoline and diesel fuel are made from crude oil. fossil energy sources. However, different chemical properties require different types of engines.
For gas engines, spark plug Ignites a mixture of compressed fuel and air. Similar to striking flint against another stone, hundreds of thousands of volts are used to create an electric arc that starts combustion.
Diesel fuel is more difficult to ignite and burns more slowly than gasoline. However, if compressed enough, it will ignite without sparking. This higher compression also results in higher efficiency, so vehicles with diesel engines Get more miles per gallon. This is important to transport goods and people as economically as possible. This is one reason why most buses, trains and lorries run on diesel.
Diesel engines tend to be more expensive than gas engines because they require sturdy parts to withstand the high temperatures and pressures they generate. But they also last longer than a gasoline engine. This is a plus for vehicles such as long-haul trucks that need to drive hundreds of thousands of miles between engine overhauls.
So why do passenger cars use gasoline? One reason is that diesel engines have higher compression and temperatures, which make them louder, especially at high frequencies that humans find unpleasant. Diesel engines also have higher levels of particulate pollutionknown as PM 2.5, associated with many human health risks.
These trade-offs typically lead consumers to prefer cheaper, quieter gasoline engines for cars they drive for work or pleasure. Efficient and long-lasting diesel engines are more attractive to companies that transport goods or large numbers of people.
Beyond the internal combustion engine
In the future, there may be no use of gasoline or diesel for transportation at all. Some cars and light trucks (models known as hybrids) already run on gasoline or diesel, along with batteries and electric motors, or completely on electricity. And cities across the United States Investing in an electric school busthey pollute less than diesel buses and are cheaper to maintain.
Hybrid, plug-in hybrid, and battery electric vehicles promise to deliver: emissions are much lower No toxic gases or carbon dioxide are emitted, especially when recharged with electricity generated from renewable energy such as wind or solar power. these vehicles it will be quiet than gasoline or diesel models. Maintenance costs are lower This is because there are fewer moving parts. Gasoline and diesel cars will continue to be used for years to come, but they are no longer at the forefront of transportation innovation.
Michael Leamy is the Woodruff Endowed Professor of Mechanical Engineering at Georgia Tech. This article is republished from conversation under Creative Commons License. please read original article.
