Compressor Blade Gust Response to Attached and Separated Flow Forcing Functions

  • Kuk H. Kim
  • Sanford Fleeter
Conference paper


A series of experiments are performed to investigate the fundamental flow forcing function phenomena generating different blade row gust responses, in particular attached and separated flow forcing functions generated with NACA 0024 airfoils. Two NACA 0024 airfoils are installed in an extensively instrumented axial flow compressor inlet to generate the periodic 2-E unsteady aerodynamic forcing functions to the first stage rotor. These forcing functions are measured with a rotating cross hot-wire, with the resulting rotor blade row unsteady aerodynamic gust response measured with dynamic pressure transducers embedded in the rotor blade over a range of steady loading levels. Appropriate rotor blade gust response unsteady aerodynamic data are then correlated with appropriate predictions. These experiments clearly show that the forcing function generator fluid dynamics is significant with regard to the resulting unsteady aerodynamic gust response of the downstream airfoil row.


Rotor Blade Force Function Separate Flow Suction Surface Unsteady Pressure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


\({\bar C_1}\)

steady lift coefficient


pressure surface complex unsteady pressure coefficient


suction surface complex unsteady pressure coefficient

ΔCp, CΔp

complex unsteady pressure difference coefficient

\({\bar C_{pi}}\)

steady pressure coefficient at ith chord position

\({\bar C_{p,p}}\)

pressure surface steady pressure coefficient

\({\bar C_{p,s}}\)

suction surface steady pressure coefficient

\(\Delta {\bar C_p}\)

steady pressure difference coefficient


rotor relative flow incidence angle


mean rotor relative flow incidence angle


1st harmonic of Fourier decomposed pressure

\({\bar P_{exit}}\)

static pressure at rotor exit


streamwise gust component


1st harmonic streamwise gust component


flow velocity or wheel speed


transverse gust component


1st harmonic transverse gust component

\({\bar V_x}\)

mean axial velocity


instantaneous rotor relative velocity

\(\bar W\)

mean rotor relative velocity


absolute flow angle

\(\bar \alpha \)

mean absolute flow angle


rotor relative flow angle

\(\bar \beta \)

mean rotor relative flow angle


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Copyright information

© Springer-Verlag New York, Inc. 1993

Authors and Affiliations

  • Kuk H. Kim
    • 1
  • Sanford Fleeter
    • 1
  1. 1.School of Mechanical EngineeringPurdue UniversityWest LafayetteUSA

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