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Herein, the energy performance of photovoltaic noise barriers (PVNBs) with cassette and shingles built‐on designs is evaluated using imec's energy yield framework. The simulation is validated through on‐site electrical and thermal measurements, and then the same design is employed for a case study near E19 road in Belgium using different scenarios. To optimize the energy yield, variations in the noise barrier height, orientation, and PV module tilt are introduced. The energy yield is then simulated to identify the optimal combination of parameters to maximize energy production. The results show that the cassette built‐on PVNB with fixed cassette distance provides higher energy yield throughout the year compared to other scenarios, and a low‐rise noise barrier is more energy‐efficient due to reduced shading effects. Sound pressure simulation conducted in COMSOL reveals that the cassette built‐on and shingles built‐on have comparable performance in sound reduction, and high‐rise noise barriers with small tilts (20°–40°) are optimal for sound pressure attenuation. [ABSTRACT FROM AUTHOR]

Individual Head-Related Transfer Functions (HRTFs) are necessary for the accurate rendering of virtual scenes. However, their acquisition is challenging given the complex pinna shape. Numerical methods can be leveraged to compute HRTFs on meshes originating from precise scans of a subject. Although photogrammetry can be used for the scanning, its inaccuracy might affect the spatial cues of simulated HRTFs. This paper aims to assess the significance of the photogrammetric error affecting a Neumann KU100 dummy head scan. The geometrical differences between the photogrammetric scan and a laser scan are mainly located at the pinna cavities. The computed photogrammetric HRTFs, compared to measured and simulated data using objective and perceptually inspired metrics, show deviation in high frequency spectral features, stemming from the photogrammetric scanning error. This spectral deviation hinders the modelled elevation perception with photogrammetric HRTFs to levels comparable to renderings with nonindividual data. Extracting the photogrammetric geometry at individual ear cavities and merging it to the laser mesh, an assessment of the influence of the inaccuracy at different pinna structures is conducted. Correlation analysis between acoustic and geometrical metrics computed on the results is used to identify the most relevant geometrical metrics in relation to the HRTFs.

Common multi-frequency solution strategies for acoustic systems are either associated with high computational costs or resort to model reduction strategies, which potentially induce considerable approximation errors. In that context, this work proposes a fast multi-frequency solver for acoustic Boundary Element Method (BEM) analyses that combines conventional preconditioners with an accelerated recycling strategy, achieving in that way a fast and accurate iterative solution. Specifically, by approximating both the system and the related preconditioner by individual affine expressions, an upfront Galerkin projection on a global deflation basis is facilitated, therefore enabling the deployment of the accelerated recycling scheme. The latter acts by accelerating the construction of the related deflation projectors, therefore leading to a significantly faster recycling procedure. Finally, the efficiency of the global deflation basis is guaranteed through an Automatic Krylov subspaces Recycling for Deflation (AKR-D) [D. Panagiotopoulos, W. Desmet and E. Deckers, An accelerated subspaces recycling strategy for the deflation of parametric linear systems based on model order reduction, Comput. Methods Appl. Mech. Eng. 403 (2023) 115765] algorithm and thus, the cumulative number of iterations required by an iterative solver within a frequency sweep is drastically decreased. The proposed multi-frequency solver is tested on two industrially relevant examples of an interior and an exterior scattering problem, benchmarked against the traditional solution strategies. [ABSTRACT FROM AUTHOR]

While acoustic analysis with the finite element method is commonly done under the assumption that the source location is stationary, this is not always a valid assumption. This paper derives a method to simulate moving sound sources using an unfitted mesh approach, where the source boundary is described by cutting through elements, known as the cut finite element method (cutFEM). By using such an approach the mesh stays static during simulation, even for large source movements, thus avoiding expensive re-meshing or mesh morphing steps. To be able to describe a wide variety of acoustic sources, both sources with a large and thin thickness are considered. Several time integration schemes are assessed and a method to determine the stability of the resulting time-varying system of equations is derived. The paper concludes by demonstrating the derived methods with two examples, where it is shown that the unfitted mesh approach is a viable way to simulate moving sources. [ABSTRACT FROM AUTHOR]