Aerodynamic-Rotordynamic Interaction in Axial Compression Systems—Part I: Modeling and Analysis of Fluid-Induced Forces

摘要: This paper presents a first principles-based model of the fluid-induced forces acting on rotor an axial compressor. These are primarily associated with presence nonuniform flow field around rotor, such as that produced by tip clearance asymmetry. Simple, analytical expressions for functions basic quantities obtained. allow intuitive understanding nature and-when combined rudimentary compressor (the Moore-Greitzer model)-enable computation function geometry, torque and pressure-rise characteristics, operating point. The predicted also compared to recently published measurements more complex models, found be in reasonable agreement. elucidates comprise three main contributions: fluid turning blades, pressure distribution unsteady momentum storage within rotor. confirms recent efforts orientation is locked nonuniformity, not asymmetry traditionally assumed. force contributions shown comparable magnitudes-and therefore equal importance-for points between design point peak characteristic. Within this range, both forward backward whirl tendencies he possible. work extends developing complete, yet compact, description it accounts all relevant contributions, tangential radial, may influence dynamics Hence constitutes essential element consistent treatment rotordynamic stability under action forces, which subject Part II paper.