Albond - Cylinder liner composite technology from MAHLE GmbH. · Alumina-Silica Fibers - Alumina (aluminum oxide) and silica (silic

Glossary Albond - Cylinder liner composite technology from MAHLE GmbH. Alumina-Silica Fibers - Alumina (aluminum oxide) and silica (silicon oxide) are used to reinforce MMC liners in Al-Si engines. Alusil - Alloy of aluminum containing silicon patented by Kolbenschmidt Aluminium-Technologie GmbH. Asperity Contact - Refers to the roughness of a contact surface. Even surfaces that appear to be smooth have a roughness to them on a microscopic scale. Atkinson Cycle - The intake valve closing is delayed until 20 to 30% of the compression stroke has taken place. Although some of the intake charge is lost, an Atkinson Cycle engine benefits from an increased expansion ratio resulting in greater efficiency at higher engine speeds. The loss of low end torque is the tradeoff. Typically Atkinson cycle engines are used in hybrid vehicles, like the Toyota Prius. BDC - Bottom Dead Center, referring to engine timing, more specifically the position of the engine where the piston is at its lowest position in the cylinder bore. Biral Cylinder - A cylinder with an iron liner and aluminum cooling fins. The Porsche 912 used biral type cylinders that had an iron bore with aluminum fins, providing slightly better cooling than a cast iron cylinder but nowhere near as good as a Chromal, Ferral, or Nikasil cylinders. Boost - In a forced induction engine, boost refers to intake charge above atmospheric pressure. Boundary Lubrication - The lubrication regime where oil film thickness is reduced to the point where solid surfaces can make contact with each other. Chemical Desorption - The release of one substance from another. Chromal Cylinder - Hard chrome has been used for cylinder wear surfaces for many years. In this case, Porsche used aluminum cylinders with chrome bores that were dimpled to provide improved lubrication, as chrome has poor oiling characteristics. Lycoming is another example of a manufacturer that uses hard chrome in their FAA approved aircraft engines. CO2 - Emissions released during the combustion of fossil fuels account for the majority of greenhouse gasses. Coefficient of Friction - The amount of friction between two moving surfaces. This is symbolized by the Greek character μ, is dimensionless, and has no units. Combustion Byproducts - Gasses and small particles emitted through incomplete combustion. Compression Ratio - The ratio of the maximum to minimum volume of a cylinder in an internal combustion engine. DEXOS - This standard was introduced by GM to work in tandem with their Oil Life Monitoring System to provide optimal fuel economy, extend emissions systems component life, and extend oil change intervals. LN Engineering Technical Library. Copyright ©2019 LN Engineering LLC