Experimental Methods for Evaluating Components of Turbomachinery, for Use in Automotive Fuel Cell Applications

Abstract

This paper describes methods and test beds for components of turbomachinery, for use in automotive fuel cell applications at the Ostfalia University of applied sciences. Turbomachinery for use in fuel cell applications is subject to different requirements than those of conventional turbochargers. Therefore, the turbine and the air bearings of an electrical turbocharger will be subject to evaluation. The different boundary conditions in comparison to conventional turbochargers, with less heat and high humidity from the fuel cell, are especially of interest. Air bearings affect the friction and the vibrations/oscillations of the shaft. The methods and test beds need to fulfill the requirements of these types of turbomachinery. The friction test bed is modified with a new coupling solution, to ensure that the driving electric motor in combination with the shaft of the test component complies with the strict tolerances. For this, a magnetic coupling, for use in high-speed applications, is developed and tested on the friction test bed. The fuel cell turbine was adapted to the hot gas test bed and extended turbine maps are determined. To reach high humidity conditions of a fuel cell application, a water injection system is integrated into the test bed.

Keywords

• fuel cell
• turbomachinery
• hot gas test bed
• heat flows
• extended turbine maps
• friction test bed