Design and numerical simulation of an air turbine for a high frequency tool spindle

Abstract

The increasing demand for micro structures and micro parts requires micro tools and precision machines. Furthermore, tool spindles with a very high rotational speed and low run out error are needed to get feasible cutting conditions while machining micro structures and micro parts. The research described in this paper investigates a parameter performance study on an air turbine for a high frequency air bearing spindle, taking into account the inlet nozzle diameter, the air turbine diameter and the gap size between air turbine and housing. The study was performed by computational fluid dynamic (CFD) simulations of the air turbine. The influence of each parameter was analysed and compared to each other. This resulted in a parameter combination that provides the highest power output for the tool spindle.