A new miniature static gas bearing turboexpander with a shaft diameter of 6mm
a wheel diameter of 9mm
and a designed rotation speed of 300 000 r/min was developed on the basis of optimum design. The structure characteristics of the prototype developed were investigated. The preliminary mechanical and thermodynamic performance of the prototype was experimentally examined. The results show that the prototype has obvious features such as small vibration
stable operation and high efficiency
and the prototype can run at more than 342 000 r/min reaching 15% over-speed. Moreover
the temperature drop can be 42 ℃ within 45 minutes when the driving pressure increases from 0 to 0.27 MPa at the room temperature of 23 ℃ for the prototype without recuperators. The experimental verification shows that the mechanical and thermodynamic performance of the prototype can meet the requirement.
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references
EVANS J C, NELLIS G F. Design and test of hydrostatic gas Bearings for a hybrid cryogenic refrigerator[C]∥ ASME International Mechanical Engineering Congress. Washington, USA:ASME, 2003:67-76.
WAUMANS T, VLEUGELS P, PEIRS J, et al. Rotor dynamic behavior of a micro-turbine rotor on air bearings: modeling techniques and experimental verification [C]∥ Proceedings of International Conference on Noise and Vibration Engineering. Lenven, Belgium: Katholieke Universiteit Leuven, 2006: 181-198.
KOUSUKE I, MOTOHIDE M, SUSUMU T, et al. Experimental verification of the feasibility of a 100W class micro-scale gas turbine at an impeller diameter of 10 mm [J]. Journal of Micromechanics and Micro Engineering, 2006, 16(9):254-261.
KOUSUKE I, SHUJI T, SHINICHI T, et al. Development of high-speed micro-gas bearings for three-dimensional micro-turbo machines [J]. Journal of Micromechanics and Micro Engineering, 2005, 15(9):222-227.
SHUJI T, KOUSUKE I, SHINICHI T, et al. Turbo test rig with hydroinertia air bearings for a palmtop gas turbine [J].Journal of Micromechanics and Microengineering, 2004, 14(11):1449-1454.
EPSTEIN A H. Millimeter-scale, micro-electro-mechanical systems gas turbine engines [J].ASME Journal of Engineering for Gas Turbines and Power, 2004, 126(2):205-226.
EHRICH F F, JACOBSON S A. Development of high-speed gas bearings for high-power density microdevices [J]. ASME Journal of Engineering for Gas Turbines and Power, 2003,125(1):141-148.