A Microfabricated Spiral-Groove Turbopump Supported on Microball Bearings

作者：Waits Christopher Mike^*; McCarthy Matthew; Ghodssi Reza

来源：Journal of Microelectromechanical Systems, 2010, 19(1): 99-109.

DOI：10.1109/JMEMS.2009.2035525

• Microelectromechanical systems (MEMS) bearings
• micropumps
• microturbines
• power MEMS
• turbopump

The development of a microfabricated turbopump that is capable of delivering liquid fuel with the flow rates and pressures required for portable power generation is reported. The device is composed of a spiral-groove viscous pump driven by a radial in-flow microturbine and supported using a newly developed encapsulated microball bearing. A planar-contact bearing raceway is employed using 285-mu m-diameter 440C stainless steel microballs. A modification to the raceway geometry, as compared to previous designs, has enabled repeatable operation of the microturbine at speeds up to 87 000 r/min, showing negligible variations in performance for over 6 h and 3.8 million revolutions. Pumping has been demonstrated with water as the working fluid for flow rates of 10-80 mL/h and pressures rises of up to 8.2 kPa. This is the first application to incorporate an encapsulated microball bearing support mechanism, to achieve rotational speeds in excess of 50 000 r/min using a contact bearing, and to demonstrate reliable operation of more than 1 million revolutions. [2009-0123]

• 出版日期2010-2