𝔖 Bobbio Scriptorium
✦   LIBER   ✦

An experimental study of propeller noise due to cyclic flow distortion

✍ Scribed by S. Subramanian; T.J. Mueller

Publisher
Elsevier Science
Year
1995
Tongue
English
Weight
943 KB
Volume
183
Category
Article
ISSN
0022-460X

No coin nor oath required. For personal study only.

✦ Synopsis

Large scale non-uniformities in the approach flow to a propeller result in periodic unsteady blade forces that radiate tonal noise at the blade passing frequency and its higher harmonics. The current research experimentally investigates the free-field directivity of a four-bladed propeller interacting with matched and mismatched cyclic distortions. The study employs non-uniform flow generators that provide a three-cycle and four-cycle azimuthal distortion of the flow field. As the inflow distortions contain just one dominant Fourier mode, a well-defined axisymmetric free-field directivity exists only for the fundamental tone. Higher harmonics, originating from small scale flow gradients, have a random directivity. An extensive comparison of the measured tonal noise levels with the theoretical predictions shows an excellent agreement, both in magnitude and directivity.

πŸ“œ SIMILAR VOLUMES

Experimental study of annoyance due to l
Experimental study of annoyance due to low frequency environmental noise
✍ R.N. Vasudevan; Colin G. Gordon πŸ“‚ Article πŸ“… 1977 πŸ› Elsevier Science 🌐 English βš– 551 KB

We have carried out a study of a particular environmental noise phenomenon which appears to be a cause of real and severe disturbance to certain people. The study has been based on fieM measurements and on laboratory studies and questioning involving two people who have suffered from this problem fo

An experimental study of probe distortio
An experimental study of probe distortions to the structure of one-dimensional flames
✍ Owen I. Smith; David W. Chandler πŸ“‚ Article πŸ“… 1986 πŸ› Elsevier Science 🌐 English βš– 654 KB

In this study we have examined the effect of a molecular-beam mass-spectrometer sampling probe on the structure of a fiat H2-O2-Ar flame doped with a small amount of HCN. Relative CN concentration and CN rotational temperature fields were obtained by laser-induced fluorescence using the R(0) through

Enhancement in mass transfer due to moti
Enhancement in mass transfer due to motion of a particle: An experimental study
✍ A. K. Verma; D. P. Rao πŸ“‚ Article πŸ“… 1988 πŸ› American Institute of Chemical Engineers 🌐 English βš– 530 KB

The understanding of the mechanism of wall-to-bed heat and mass transfer in liquid-fluidized beds requires knowledge of the effect of the motion of individual particles on transfer processes. Experimental studies on the enhancement in mass transfer due to motion of a particle in the proximity of the