Abstract
Pressure expansion is required in many process applications, and the excess process energy ends up being dissipated as heat. An Example is the throttling process of compressed air systems. Using a micro air turbine generator that can produce electricity under pressure expansion, the wasted energy can be recovered. This paper proposes a millimeter-scale air turbine which can be used for electric generation. The air turbine is based on a single-stage axial reaction turbine with a rated rotational speed of 100,000 RPM and a rated mechanical power output of 150 W. A CFD software (STAR-CCM+) was used to predict the performance of the micro air turbine at different operating conditions. Losses due to skin friction and geometry factor are discussed. The completed rotor assembly of the micro air turbine was tested to measure the performance.