What type of compression method is typically used for turbo-chargers and superchargers?

In turbochargers and superchargers, the method typically used for compression is centrifugal compression. This process involves the use of a rotating impeller that accelerates the air radially outward from the center of the impeller to the outer edge. As the air moves outward, it increases in velocity and is then slowed down in a diffuser, converting the kinetic energy into pressure energy.

Centrifugal compressors are favored in these applications because they can efficiently handle large volumes of air and provide a significant boost to the engine's intake pressure, which is essential for improving performance in internal combustion engines. Their design allows for a compact form factor and higher reliability, making them suitable for automotive use.

The other methods mentioned, such as axially or co-axially, refer to different types of flow arrangements and are typically not used in the context of turbochargers and superchargers. These alternatives do not efficiently compress air in the same way or are suited to different applications outside the realm of forced induction in automotive engines.