Showing papers by "Walter F. O'Brien published in 1986"
01 Apr 1986
TL;DR: The performance of the complex cepstrum as used to recover wavelets in the presence of distorted echoes and noise is studied using simulated signals.
Abstract: The performance of the complex cepstrum as used to recover wavelets in the presence of distorted echoes and noise is studied using simulated signals. The distortions and noise are chosen to be representative of practical applications encountered in acoustic source location. On the whole the complex cepstrum is seen to perform well for the situations considered.
3 citations
09 Jul 1986
TL;DR: In this article, a single-stage axial-flow fan was instrumented with blade-mounted high frequency pressure transducers to map out the unsteady pressure field produced on fan rotor blades by interaction with downstream struts.
Abstract: In the present study of the unsteady pressure field produced on fan rotor blades by interaction with downstream struts, a single stage, low speed axial-flow fan was instrumented with blade-mounted high frequency pressure transducers. In addition, stationary pressure problems were used to map out the flowfield. Fluctuating pressure measurements are presented for blade midspan and 85-percent span on both the suction and pressure surfaces of the rotor blades at several positions of the downstream struts, and for two different flow coefficients. The strut is found to produce an effect on the unsteady pressure field on the rotor blades; this effect exceeds that due to the stator at design rotor-stator-strut spacing, but it rapidly declines as the struts are moved downstream.
2 citations