Naslov
Implementation and validation of acoustic wave propagation model

Autori
Azenić, Adam

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, diplomski rad, diplomski

Fakultet
Fakultet strojarstva i brodogradnje

Mjesto
Zagreb

Datum
25.03

Godina
2016

Stranica
153

Mentor
Jasak, Hrvoje

Ključne riječi
Linearised Euler Equations ; acoustic wave propagation ; OpenFOAM-extend ; Finite Volume Method

Sažetak
Noise pollution negatively influences the quality of people’s lives and the consequences on the health are often significant. Therefore, the problem of predicting the sound sources and propagation of acoustic waves is an everyday growing issue that the engineers and scientists encounter. In this thesis the implementation, verification and validation of the Linearised Euler Equa- tions (LEE), which govern the acoustic wave propagation, have been conducted. The LEEs have been implemented as a stand-alone solver, using OpenFOAM-extend C++ libraries. The system of LEEs has been discretised by using the conservative Finite Volume Method (FVM). Verification and validation of the solver have been carried out with three test cases, comparing the results with analytical solutions. The grid convergence study for the validation test cases has been carried out. The simplified method for the sound source prediction using RANS pre- dicted turbulence data has been implemented and tested on the simulation of noise generated by 2D mixing layer. Results have shown that the solutions obtained with the LEE solver converge towards the analytical solutions. Simulation of acoustic wave reflection off a wall has shown that the nu- merical predictions of the reflected and non-reflected wave give solutions of practically the same accuracy. Results for later time instants contain spurious waves, reflected off the open boundaries, due to inadequate boundary condition used in simulations. It can be concluded that the implementation of sound propagation method has been success- fully conducted, as evidenced by the results of three test cases. It is shown that the propagation of acoustic waves in an uniform mean flow can accurately be computed with the implemented solver. The method for the sound source generation needs improvements, what together with the implementation of a non-reflecting boundary condition remains a task for future research.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

POVEZANOST RADA