109 citations · 118 across the 7 of their papers we have counts for
10 papers
Shape calculus and automatic differentiation for multi-phase level-set topology optimisation with unfitted finite elements
Zachary J. Wegert, Martin Berggren, Vivien J. Challis
We present shape calculus techniques and a scalable automatic shape differentiation framework for multi-phase topology optimisation on unfitted discretisations defined by several l…
Multilayer Dual-polarized Microstrip Antenna Design by Topology Optimization with Enhanced Bandwidth
Pan Lu, Eddie Wadbro, Viktor Lundström +3
Dual-polarized (DP) microstrip antennas are utilized in wireless systems for efficient data transmission. However, their bandwidth is typically very limited. In this contribution,…
Topology optimization of decoupling feeding networks for antenna arrays
Pan Lu, Eddie Wadbro, Jonas Starck +2
Near-field and radiation coupling between nearby radiating elements is unavoidable, and it is considered a limiting factor for applications in wireless communications and active se…
A better compression driver? CutFEM 3D shape optimization taking viscothermal losses into account
Martin Berggren, Anders Bernland, André Massing +2
The compression driver, the standard sound source for midrange acoustic horns, contains a cylindrical compression chamber connected to the horn throat through a system of channels…
Shape calculus for fitted and unfitted discretizations: domain transformations vs. boundary-face dilations
Martin Berggren
Shape calculus concerns the calculation of directional derivatives of some quantity of interest, typically expressed as an integral. This article introduces a type of shape calculu…
Investigations of an effective time-domain boundary condition for quiscent viscothermal acoustics
Linus Hägg, Martin Berggren
Accurate simulations of sound propagation in narrow geometries need to account for viscous and thermal losses. In this respect, effective boundary conditions that model viscotherma…
Well-posed variational formulations of Friedrichs-type systems
Martin Berggren, Linus Hägg
All finite element methods, as well as much of the Hilbert-space theory for partial differential equations, rely on variational formulations, that is, problems of the type: find $u…
On the well-posedness of Galbrun's equation
Linus Hägg, Martin Berggren
Galbrun's equation, which is a second order partial differential equation describing the evolution of a so-called Lagrangian displacement vector field, can be used to study acousti…
Acoustic boundary layers as boundary conditions
Martin Berggren, Anders Bernland, Daniel Noreland
The linearized, compressible Navier-Stokes equations can be used to model acoustic wave propagation in the presence of viscous and thermal boundary layers. However, acoustic bounda…
A Nitsche-type Method for Helmholtz Equation with an Embedded Acoustically Permeable Interface
Esubalewe Lakie Yedeg, Eddie Wadbro, Peter Hansbo +2
We propose a new finite element method for Helmholtz equation in the situation where an acoustically permeable interface is embedded in the computational domain. A variant of Nitsc…