Unsteady Three-Dimensional Flow in a Single-Stage Transonic Fan: Part II—Unsteady Stator Exit Flow Field

Abstract

Detailed unsteady aerodynamic measurements have been taken in a single-stage transonic fan with a very high stage-hub loading. Two-dimensional dynamic yawmeter probes, capable of measuring mean levels and fluctuations in stagnation pressure, static pressure, and yaw angle have been traversed at rotor exit and downstream of the stator, along with several types of pneumatic three-dimensional probe. Part I describes measurements taken at rotor exit. This paper, Part II, describes measurements taken at stator exit when the fan was operating at near-peak efficiency, on the design speed characteristic. The measurements indicate the effects of Rotor-Stator interaction on the development of the viscous endwall-corner flows at the hub and casing. In addition, they illustrate that significant changes in stagnation pressure level occur within much of the stator exit flow field during the rotor passing cycle.