A microscale, high-speed compressor impeller (12 mm diameter, 800,000 rpm) was tested for feasibility in regard to aerodynamic performance. The compressor was designed for application in a first-sized gas turbine generator. To survive high stresses at such high temperatures, the rotor was manufactured as a single turbine/compressor/shaft unit in silicon nitride, by the Mold SDM process. Performance testing was conducted in a cold-flow rig at reduced speed of 420,000 rpm. Results from a CFD code compared favorably to measured data at this speed. Extrapolation from test conditions to full design speed was accomplished by application of CFD applied at both speeds.

Issue Section:
Gas Turbines: Microturbines and Small Turbomachinery
Keywords:
micromechanical devices, gas turbines, silicon compounds, thermodynamics, micromachining
Topics:
Compressor impellers, Compressors, Computational fluid dynamics, Design, Flow (Dynamics), Gas turbines, Manufacturing, Microscale devices, Pressure, Radial flow, Rotors, Silicon nitride ceramics, Turbines, Ceramics, Blades, Temperature, Industrial ceramics, Impellers
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 by ASME
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