READ ME File For dataset 'Aerofoil broadband noise reductions through double-wavelength leading edge serrations; a new control concept'

Dataset DOI: 10.5258/SOTON/D0599

ReadMe Author: Chaitanya Paruchuri, ccp1m17@soton.ac.uk, ISVR, University of Southampton

This dataset supports the publication:

Paruchuri, C., Joseph, P., & Kim, J. (2018). Aerofoil broadband noise reductions through double-wavelength leading edge serrations; a new control concept. Journal of Fluid Mechanics. 

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The *.mat files contains the experimental data for the paper. In particular:

Figure3: Comparison between the measured axial velocity spectra and theoretical Von Karman spectra.

Figure4: Comparison of correlation coefficient function measured at 40 m/s compared with Von Karman interpolation formula using the integral length scale $\Lambda_{uu,x}=8$ mm

Figure5: Comparison of sound pressure levels at the $90^\circ$ microphone location between Amiet's analytic prediction (solid red) and experimental (dotted black) for a fixed chord ($c_0$=150 mm) and varying jet velocities ($U$ = 20, 40, 60 and 80 m/s).

Figure6: Acoustic performance of double-wavelength serrations for $\lambda_1/c_0=0.033 \,\, \lambda_2/c_0 =0.067, h/c_0=0.1, \phi=0$ and flow velocity $U$=60m/s. (\ref{hwplot2}: Single-wavelength $\lambda_1$; \ref{hwplot1}: Single-wavelength $\lambda_2$; \ref{hwplot3}: Double-wavelength serration)

Figure7: Acoustic performance of double-wavelength serrations for $\lambda_1/c_0 =0.033 \: \& \: \lambda_2/c_0 =0.067, h/c_0=0.167$, U=60m/s at varying phase $\phi$ ratios of 0, $\pi/4$, $\pi/2$. (\ref{hwplot2}: $\phi=0$; \ref{hwplot3}: $\phi=\pi/4$; \ref{hwplot3}: $\phi=\pi/2$).

Figure8: Influence of serration wavelength on noise reduction at a fixed peak-to-root amplitude $2a=0.33$ \& ($\lambda_1/\lambda_2=0.5$) at jet velocity 60 $m/s$.

Figure9: Variation of coherence for different spanwise separation distance $\lambda/\Lambda$.

Figure10: Comparison between measured and predicted additional noise reduction spectra ($\Delta \text{PWL}_I$) for a double-wavelength serration with $\lambda/\Lambda=0.95$ and $h/c_0=0.13$. Predictions are based on coherence estimates from Figure 9.

Figure11: Influence of flow velocity on noise reduction due to double-wavelength serration profiles.

Figure12: Total sound power reductions level ($\Delta \text{PWL}$) for  single, double-wavelength serrations on 3-D aerofoils of $\lambda_1/c_0 =0.067 \: \& \: \lambda_2/c_0 =0.13$, $\lambda/\Lambda=1.91$, $2a/c_0=0.33$, U=60 $m/s$. (\ref{aero1}: Single-wavelength, $\lambda_1$ (Aerofoil); \ref{aero2}: Single-wavelength, $\lambda_2$ (Aerofoil); \ref{aero3}: Double-wavelength (Aerofoil); \ref{aero4}: Double-wavelength (Flat plate))


Date of data collection: from January 2016 - July 2017

Geographic location of data collection: University of Southampton, U.K.


Dataset available under a CC BY 4.0 licence


Publisher: University of Southampton, U.K.


Date: July 2018