Centrifugal-type supercharger

A centrifugal supercharger is a specialized type of supercharger that makes use of centripetal force in order to push additional air into an engine. Increased airflow into an engine allows the engine to burn more fuel, which results in increased power output of the engine. Centrifugal superchargers are generally attached to the front of the engine via a belt-drive or gear-drive from the engine’s crankshaft.

The centrifugal supercharger is used in many applications including, but not limited to, automotive, truck, marine, aircraft, motorcycles and UTV’s. Of these applications, they are most commonly utilized for increasing horsepower in street vehicles and race applications. While the first practical centrifugal compressor was designed in 1899, centrifugal superchargers evolved during World War II with their use in aircraft, where they were frequently paired with their exhaust driven counterpart, the turbosupercharger. This term refers to the fact that turbochargers are a specific type of centrifugal supercharger, one that is driven by a turbine.

Lately, centrifugal superchargers have become very common in today’s performance automotive world. Superchargers are sometimes installed as original equipment on some vehicles manufactured today. Centrifugal supercharging creates an efficient, compact and intercooler friendly means to boost horsepower in both gasoline and diesel engines for a wide variety of watercraft, land craft and aircraft.

Centrifugal superchargers have become popular in the aftermarket as a bolt-on addition to improve performance. By design, centrifugal superchargers allow for easy integration of air-to-air or air-to-water intercooling. Several companies build centrifugal superchargers and also offer them as complete systems which can be easily installed by a mechanic or the auto enthusiast at home.

Superchargers in aircraft play an important role by providing additional air pressure at higher altitudes. Because air pressure decreases at high altitudes, air compression is necessary in order to keep the airplane’s engine running at maximum efficiency.

The four main components of a centrifugal supercharger are the volute (compressor housing), diffuser, impeller and transmission. Volutes are typically cast into a form from aluminum rather than other metals due to the combination of strength, weight, and resistance to corrosion. Volutes are then precision machined to match the impeller design. Impellers are designed in many configurations, and Euler’s pump and turbine equation plays an important role in understanding impeller performance. Impellers are often formed by casting metals into a form and then machined, with the highest quality impellers machined from solid billet.

The transmission provides a step-up ratio from the input shaft (driven from the engine crankshaft) to the output shaft, to which the impeller attaches (it is not uncommon for centrifugal supercharger impeller speeds to exceed 100,000 rotations per minute). The basic components of the gear drive centrifugal transmission are shafts, gears, bearings, and seals. Because of the high speeds and loads the transmission must endure, components are machined, ground and assembled to extremely close tolerances.

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Wikipedia