Views: 0 Author: by Cummins Inc., Global Power Technology Leader Publish Time: 2023-08-30 Origin: https://www.cummins.com/news/2023/06/27/what-makes-diesel-engines-advanced-diesel-engines
Invented in the 1890s, diesel engines have been powering our world since soon after Rudolf Diesel filed his first patent. But how has diesel technology changed over the years, and what makes an engine an advanced diesel engine?
Let’s take a look at today’s diesel engines and how Cummins Inc’s innovations have improved and enhanced this technology.
There are two ways to designate the types of diesel engines. The most common way is by size—small, medium, and large.
Small diesel engines produce up to 288 horsepower, usually found in small trucks or automobiles.
Medium diesel engines produce up to 1,000 horsepower, commonly used in heavy-duty trucks.
Large diesel engines produce over 1,000 horsepower, typically used to power trains, ships, and other large vehicles or equipment.
Another specification that sets apart different types of diesel engines is the number of strokes in the combustion cycle, either four-stroke or two-stroke. Four-stroke diesel engines have four stages—intake, compression, power and exhaust. During these four stages, the piston changes positions on each stroke. The two-stroke engine combines the intake and compression stroke, and the power and exhaust stroke.
As diesel technology progressed, the two-stroke engine, once prized for its ability to produce more power than four-stroke engines of the same size, was phased out due to the large quantity of pollution it produced as well as the exorbitant wear and tear that caused frequent breakdowns.
Four-stroke diesel engines came out on top as the superior type, and manufacturers have continued to improve them over the years.
An important advancement with diesel engines is improved fuel efficiency with fewer emissions. In one study, diesel vehicles show 24% greater fuel efficiency in city driving and 29% on the highway. At Cummins, our broad portfolio of advanced clean diesel engines meets the most stringent emission standards in the United States.
Features of the diesel engine that have been tweaked to make them more advanced are details like longer oil-drain intervals or maintenance-free filters. Our advanced diesel engines are designed to last longer with less upkeep. With vast experience in diesel engine optimization, along with reducing emissions through combustion and aftertreatment solutions and hybrid technologies, Cummins is dedicated to continuing the advancement of diesel engine technology.
Another way to ask this question is, “why do diesel engines have more torque?” Torque, the rotational force of the engine, is essentially the amount of work that an engine can produce. High torque diesel engines have high pulling power, especially when compared to gasoline engines of the same size. The reason for this is found in the way that diesel and gasoline engines function.
Inside of a diesel engine, the piston rises all the way to the top of the cylinder, giving the engine a higher compression ratio. Gasoline engine pistons stop short, leading to a lower compression ratio. A higher compression ratio results in air being delivered faster and at quicker combustion rates, all translating to increased torque and horsepower. Higher compression ratios also point to greater overall efficiency. We focus on turbochargers for medium- and heavy-duty diesel engines to deliver efficiency and meet strict emissions requirements.
A frequently asked question about diesel engines is, “are they clean?” The answer to that is complicated, especially when looking at older diesel engines compared to gasoline engines—older technologies are worse for the environment as they are lacking the modern diesel engine advancements. The good news, however, is that diesel engines are getting cleaner.
Diesel engines can produce pollutant emissions like carbon dioxide (CO2), nitrogen oxides (NOx) and particulate matter (PM), which are not only harmful to human health but also to the planet’s health. Reducing greenhouse gas (GHG) emissions like CO2 is especially important due to carbon’s longevity and abundance over other greenhouse gases.
Today’s clean diesel engines emit 90% less harmful emissions than engines produced before the year 2000. New innovations overtime have helped diesel engines become increasingly cleaner for our environment and the industry.
Methods like Exhaust Gas Recirculation (EGR) can help reduce NOx emissions when the combustion temperatures can be lowered. NOx can even be removed from diesel engine exhaust through additional methods, including Selective Catalytic Reduction (SCR) and Selective Non-Catalytic Reduction (SNCR). Modern diesel engines are much more efficient, producing significantly less carbon dioxide than other fuel sources. Cummins produces engines capable of removing as much as 98% of particulate matter from the exhaust.
We believe the best way to create a zero emissions future is to invest in a broad power portfolio, continuing to improve diesel efficiency in tandem with technologies like hydrogen and natural gas engines. We also offer a variety of proven emission solutions to best fit your needs, from fully integrated aftertreatment systems to individual system components.
At Cummins, we recognize that our communities and businesses depend on a healthier planet. Our destination is zero—zero emissions and zero negative impacts on the communities we serve. This ambitious goal drives us to innovate in the areas of advanced diesel, natural gas, electrification, fuel cells, alternative fuels, and advanced energy solutions. Learn more about Destination Zero and our broad portfolio of engines.