In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorization is that a supercharger is a form of forced induction that is mechanically powered (usually by a belt from the engine’s crankshaft), as opposed to a turbocharger, which is powered by the kinetic energy of the exhaust gases. However, up until the mid-20th century, a turbocharger was called a “turbosupercharger” and was considered a type of supercharger. The first supercharged engine was built in 1878 with usage in aircraft engines beginning in the 1910s and usage in car engines beginning in the 1920s. In piston engines used by aircraft, supercharging was often used to compensate for the lower air density at high altitudes. Supercharging is less commonly used in the 21st century, as manufacturers have shifted to turbochargers to reduce fuel consumption and increase power outputs.
There are two main families of superchargers defined according to the method of gas transfer: positive displacement and dynamic superchargers. Positive displacement superchargers deliver an almost constant level of boost pressure increase at all engine speeds, while dynamic superchargers cause the boost pressure to rise exponentially with engine speed (above a certain threshold). Another family of supercharger, albeit rarely used, is the pressure wave supercharger. Roots blowers (a positive displacement design) tend to be only 40–50% efficient at high boost levels, compared with 70-85% for dynamic superchargers.[citation needed] Lysholm-style blowers (a rotary-screw design) can be nearly as efficient as dynamic superchargers over a narrow range of load/speed/boost, for which the system must be specifically designed.Internals of a rotary-screw (Lysholm) supercharger ,Positive displacement pumps deliver a nearly fixed volume of air per revolution of the compressor (except for leakage, which typically has a reduced effect at higher engine speeds). The most common type of positive-displacement superchargers is the Roots-type LSA Supercharger. Other types include the rotary-screw, sliding vane and scroll-type superchargers.
If you loved this article and you simply would like to acquire more info concerning LSA Supercharger i implore you to visit our own page. The rating system for positive-displacement superchargers is usually based on their capacity per revolution. In the case of the Roots blower, the GMC rating pattern is typical. The GMC rating is based on how many two-stroke cylinders – and the size of those cylinders – that it is designed to scavenge, with GMC’s model range including 2–71, 3–71, 4–71 and 6–71 blowers. The 6–71 blower, for example, is designed to scavenge six cylinders of 71 cu in (1.2 L) each, resulting in an engine with a total displacement of 426 cu in (7.0 L)). However, because 6–71 is the engine’s designation rather than that of the blower, the actual displacement of the blower is less; for example, a 6–71 blower pumps 339 cu in (5.6 L) per revolution. Other supercharger manufacturers have produced blowers rated up to 16–71.