libAcoustics Validation

a_habib · June 22, 2015, 02:34

Hello.

I tried to validate the libAcoustics library for sound propagation based on Curle analogy using the paper ((Two and Three-Dimensional Simulation of Sound Generated by Flow Around a Circular Cylinder - 30th AIAA Aeroacoustics Conference)).
every thing was good as you can see my results except when I calculated the SPL & OASPL for different cylinder span length. The result where on the opposite, the higher SPL in my calculation was related to the shortest cylinder (in the paper was related to the longest cylinder).
any one can tell me why this happened. or is there any explanation for this result. ????
you can check my controlDit
Results1.jpg

Results2.jpg

SPL.jpg

controlDict.txt

guanjiang.chen · February 23, 2021, 05:57

Quote:

Originally Posted by a_habib

Hello.

I tried to validate the libAcoustics library for sound propagation based on Curle analogy using the paper ((Two and Three-Dimensional Simulation of Sound Generated by Flow Around a Circular Cylinder - 30th AIAA Aeroacoustics Conference)).
every thing was good as you can see my results except when I calculated the SPL & OASPL for different cylinder span length. The result where on the opposite, the higher SPL in my calculation was related to the shortest cylinder (in the paper was related to the longest cylinder).
any one can tell me why this happened. or is there any explanation for this result. ????
you can check my controlDit
Attachment 40279

Attachment 40280

Attachment 40281

Attachment 40282

Hi Ahmad,

That result seems not very bad. Do you post the spl value directly or you make some postprocess for the farfield pressure to get it?

Regards,
Guanjiang

dragazsolt · December 5, 2023, 11:31

Hi Guys,

When I run libacoustic I do not get any SPL or PSD results. I only get pressure- time signal. Do you use any special tools to get SPL or PSD?

Thanks for your info

Zsolt

guanjiang.chen · December 5, 2023, 11:34

Hi,

You can calculate SPL or PSD using Matlab. Many functions could be used.

https://uk.mathworks.com/help/signal...sults_1_pwelch

https://uk.mathworks.com/help/signal...using-fft.html

Regards,
Guanjiang

June 22, 2015, 02:34	libAcoustics Validation	#1
a_habib Member Ahmad Habib Join Date: Nov 2014 Location: Aleppo, Syria Posts: 53 Rep Power: 11	Hello. I tried to validate the libAcoustics library for sound propagation based on Curle analogy using the paper ((Two and Three-Dimensional Simulation of Sound Generated by Flow Around a Circular Cylinder - 30th AIAA Aeroacoustics Conference)). every thing was good as you can see my results except when I calculated the SPL & OASPL for different cylinder span length. The result where on the opposite, the higher SPL in my calculation was related to the shortest cylinder (in the paper was related to the longest cylinder). any one can tell me why this happened. or is there any explanation for this result. ???? you can check my controlDit Results1.jpg Results2.jpg SPL.jpg controlDict.txt guanjiang.chen likes this.

December 5, 2023, 11:31	SPL , PSD evaulation	#3
dragazsolt New Member ZsoltDraga Join Date: Jan 2011 Location: Albertirsa, Hungary Posts: 10 Rep Power: 15	Hi Guys, When I run libacoustic I do not get any SPL or PSD results. I only get pressure- time signal. Do you use any special tools to get SPL or PSD? Thanks for your info Zsolt

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December 5, 2023, 11:34		#4
guanjiang.chen Member Guanjiang Chen Join Date: Apr 2020 Location: Bristol, United Kingdom Posts: 54 Rep Power: 6	Hi, You can calculate SPL or PSD using Matlab. Many functions could be used. https://uk.mathworks.com/help/signal...sults_1_pwelch https://uk.mathworks.com/help/signal...using-fft.html Regards, Guanjiang