The short answer is that DEF, or Diesel Exhaust Fluid, is an important component in keeping heavy-duty trucks and machinery operating within federal emission guidelines. What DEF is, at a chemical level, is a combination of deionized water and urea that transform harmful nitrous oxide emissions into harmless water and gas.

Jul 03, 2018 · Small quantities of diesel exhaust fluid (DEF) are injected into the exhaust upstream of a catalyst, where it vaporizes and decomposes to form ammonia and carbon dioxide. The ammonia (NH3) is the desired product which in conjunction to the SCR catalyst, converts the NOx to harmless nitrogen (N2) and water (H2O).

How Does Def Work In Diesel Engines? Here’s everything you need to know: How Does Def Work In Diesel Engines? DEF is sprayed into the exhaust stream by an advanced injection system and then converted into ammonia on a catalyst. The ammonia breaks down dangerous NOx emissions produced by diesel engines into nitrogen and water.

Oct 09, 2018 · The DEF is added to the exhaust gas and then passed through the catalytic chamber. The catalyst itself can be composed of a variety of materials such a metals, metal oxides, perovskites and zeolites. The urea (CO (NH2)2) from the fluid reacts with the NO by: 4NO + 2CO (NH2)2 + O2 → 4N2 + 4H2O + 2CO2

Apr 13, 2018 · Here’s how it works: DEF is made by combining urea and deionized water. Urea is an organic compound made up of nitrogen, hydrogen, carbon and oxygen. When DEF is mixed with hot exhaust gases, it...

Oct 24, 2018 · How DEF Works. DEF is not a fuel additive, and has no influence on the tuning and efficiency of diesel engines. The way it works is that the fluid, an organic compound comprising urea and deionized water, is mixed with the hot gases that follow diesel combustion, breaking DEF down into ammonia and carbon dioxide.

Jul 13, 2021 · How does DEF work? “In diesel exhaust emissions systems, when we spray DEF into the diesel exhaust gases, a chemical reaction takes place. As the newly combined molecules flow through the catalyst filter in the aftertreatment system, it breaks down those components into nitrogen and water, which are harmless gasses so it’s taking harmful gases and converting …

Jan 21, 2022 · The def keyword is used to tell Python that the following block of indented code is a function. Thus we can use functions to organize the code nicely into several sections using the def keyword! I hope you now have a good understanding of the “ def ” keyword in Python!