Design, Analysis, Fabrication and Test of an Aspirated Fan Stage

A fan stage designed by means of a MISES-based quasi-3D approach (Youngren and Drela, 1991), for a pressure ratio of 1.6 at a tip Mach number of 0.7, has been analyzed by viscous 3D CFD, fabricated and tested in the MIT Blowdown Compressor. The design incorporates a rotor tip shroud and boundary layer removal on the suction surfaces of the rotor and stator and at other critical locations. The fully viscous 3D analysis enabled final detailing of the design. In tests, the stage has met its design objectives, producing the design pressure ratio of 1.6 at design speed. The mass flow removed totaled 4.7%, approximately 1.0% through slots on the suction surface of the rotor and stator, and the remainder distributed over the rotor shroud and stator hub. The measured adiabatic efficiency of the rotor for the throughflow was 96% at the design point and that for the stage was 90%. This paper presents the design, the results of the analysis and the experimental stage performance both at design and at some off-design conditions.Copyright © 2000 by ASME