Introduction Theory Implementation of library Test case Implementation of library for acoustic sound pressure and spanwise correction Aya Aihara Division of Electricity, Uppsala University, Sweden 2018-11-28 Aya Aihara Beamer slides template 2018-11-28 1 / 27
27
Embed
Implementation of library for acoustic sound pressure and ...
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Introduction Theory Implementation of library Test case
Implementation of library for acoustic sound pressureand spanwise correction
Aya Aihara
Division of Electricity,Uppsala University,
Sweden
2018-11-28
Aya Aihara Beamer slides template 2018-11-28 1 / 27
Introduction Theory Implementation of library Test case
Outline
1 Introduction
2 Theory
3 Implementation of library
4 Test case
Aya Aihara Beamer slides template 2018-11-28 2 / 27
Introduction Theory Implementation of library Test case
Outline
1 Introduction
2 Theory
3 Implementation of library
4 Test case
Aya Aihara Beamer slides template 2018-11-28 3 / 27
Introduction Theory Implementation of library Test case
Introduction
Computational aeroacoustics for noise emission
ProblemHigh cost of simulating the whole computational domain to obtain thesound pressure generated from long-span body
AimImplementation of library to calculate the total sound pressure using theflow field data of the body section in the computational domain
Aya Aihara Beamer slides template 2018-11-28 4 / 27
Introduction Theory Implementation of library Test case
Outline
1 Introduction
2 Theory
3 Implementation of library
4 Test case
Aya Aihara Beamer slides template 2018-11-28 5 / 27
Introduction Theory Implementation of library Test case
Sound propagation
Acoustic wave equation
Describes the propagation of acoustic pressure in a medium
Curle’s acoustic analogy
Considers the influence of solid boundaries upon the flow fieldSolution of the Curle’s equation
ρ(x, t)− ρ0 =1
4πc20
∂2
∂xi∂xj
∫V
TijrdV (y)
− 1
4πc20
∂
∂xi
∫S
njr(pδij − τij)dS(y)
Aya Aihara Beamer slides template 2018-11-28 6 / 27
Introduction Theory Implementation of library Test case
Sound propagation
Modified Curle’s equation
p(x, t)− p0 =1
4π
∫V
( liljc20r
Tij +3lilj − δijc0r2
Tij +3lilj − δij
r3Tij
)dV (y)
+1
4π
∫Slinj
( pδij − ˙τijc0r
+pδij − τij
r2
)dS(y)
This equation is implemented in the library.
Aya Aihara Beamer slides template 2018-11-28 7 / 27
Introduction Theory Implementation of library Test case
Spanwise correction
Correction method proposed by Kato et al. [1]
pcorr : Sound pressure generated from theentire body (L)
p : Sound pressure generated from the sectionof the computational domain (Ls)