Centrifugal compressor
The centrifugal compressor or radial compressor is a compressor in which the gas to be compressed is set in rotation by an impeller running in an adapted housing and accelerated from the inside to the outside. In the subsequent diffuser , the kinetic energy is converted into pressure. Radial compressors are designed for pressure ratios of 1.2 to 4, rarely 6.
This type of construction is widespread, especially in devices that are built in one stage, such as hand dryers , vacuum cleaners , hair dryers , but it is also used to charge internal combustion engines. The drive power comes either from the crankshaft via a transmission gear or from the exhaust gas flow of the engine via a turbine - in the latter case it is an exhaust gas turbocharger . In the past there were often jet engines with one or more centrifugal compressors. Due to the complicated flow return to the next compressor stage, a maximum of one final radial compressor stage (e.g. Pratt & Whitney Canada JT15D ) is generally used today . Axial compressors are predominantly used in large engines , as they are more suitable for the higher mass flows. A major advantage of a radial compressor is its high pressure build-up compared to an axial compressor, whose pressure build-up in one stage is only 1.2 to 1.5.
Splitblade
In contrast to an axial compressor, centrifugal compressors occasionally have two different blade types, each alternating. The main blade is the larger and extends far to the inlet opening, while the so-called split blade begins much later in the gas flow and is significantly smaller - it uses the increasing distance between the main blades.
Individual evidence
- ^ Willy JG Bräunling: aircraft engines . 2015, p. 190 , doi : 10.1007 / 978-3-642-34539-5 ( springer.com [accessed May 30, 2018]).