COMSOL Day: Acoustics
See what is possible with multiphysics simulation
Join us for a full-day online event with a special focus on acoustics. You will have the opportunity to meet with COMSOL technical staff and customers from around the world, engage in product demonstrations, and gain insight into upcoming projects and focuses within acoustics research and industry.
Topics include the analysis of loudspeakers, ultrasound and non-destructive testing (NDT), microacoustics, room acoustics, vibrations, as well as convected acoustics. We will also address topics like optimization, meshing, and solving of large acoustic models. During the presentations you will be encouraged to ask questions. Engineers from COMSOL will be able to answer and present best practices.
Feel free to invite your colleagues. View the schedule below and register for free today!
Please join us 10 minutes before the presentation starts to settle in and make sure that your audio and visual capabilities are working.
To start, we will briefly discuss the format of the day and go over the logistics for using GoToWebinar.
During this session, you will get an introduction to the latest news and trends in acoustics simulation. We will also briefly discuss some of the future developments and ideas for the Acoustics Module.
René Christensen, Acculution
The presentation will briefly go through the different categories of simulations that are most relevant for loudspeaker simulations, and show examples of linear vs. nonlinear simulations as well as stationary vs. frequency vs. time-dependent simulations. It will also be discussed how shape or topology optimization can be added to most, if not all, of these simulations in a way that the design of parts are, to some degree, determined via the simulations themselves, instead of using simulations in a trial-and-error process.
In this session, we will introduce key features within COMSOL Multiphysics® and the Acoustics Module and discuss how to solve the acoustic wave equation in order to model sound generation, propagation, absorption, and attenuation. The key features will be demonstrated by building a simple model, from applying the physics and properties of the system to the different ways to postprocess the results.
Acoustic propagation in structures with submillimeter physical features is common in the components of consumer products like mobile devices, protective grills of loudspeakers, hearing aids, and perforates used in mufflers and sound insulation. To model this accurately, you need to include thermoviscous losses in your definition of the physics. In this session, you will be introduced to modeling techniques used to capture these effects and how to model nonlinear effects in microacoustics systems.
Acoustic propagation in rooms, halls, car cabins, and other enclosed yet definitive spaces falls within the field of room acoustics. In this session, you will learn how acoustic behavior and response from the features in a room can be modeled in COMSOL Multiphysics® using both ray tracing and full-wave models, in some cases combined with each other. This feature is useful when defining submodels of, for example, a treated wall or absorber, in order to compute the angle-dependent absorption, which is then used in a ray tracing model for the room as a whole.
The analysis of acoustic phenomena in the presence of background mean flow is often referred to as convected acoustics or flow-borne noise. Applications include jet engine noise, mufflers, and perforates, all including the presence of a background flow. This session will introduce the aeroacoustics capabilities of COMSOL Multiphysics® and demonstrate examples of convected acoustics.
Naveen Indolia, SCANIA CV AB
Silencers for heavy vehicles have evolved in the past decades into after-treatment systems, which have complex structures, multiple catalyst bricks, perforated plates, microperforated plates, etc. In order to meet the acoustic targets, it is crucial for SCANIA to predict the acoustic performance of these systems during the development phase. The exhaust simulation group NXPS has developed methods to predict the behaviors of sound propagating through these systems as well as that generated within these systems.
Miguel Molerón, Metacoustic
Over the past decade, acoustic metamaterials have emerged as a new paradigm for manipulating acoustic waves. In this presentation, we show a patented vibroacoustic metamaterial concept that efficiently blocks the transmission of sound over a broad low-frequency range. The transmission loss of this solution is significantly better than what can be expected from the classical mass law. Numerical simulations, theory, and practical implementation aspects will be discussed.
Alioli Mattia and Vivek Kumar, Endress+Hauser
This work investigates flow–acoustic interaction for duct components to predict the onset of possible flow–acoustic instabilities. Components in duct systems that create flow separation can, in fact, for certain conditions and frequencies, amplify incident sound waves, and this can affect the performance of the components themselves. This vortex-sound phenomenon, due to the energy transfer between acoustic and vorticity modes in the fluid, is the origin for whistling; i.e., the production of acoustic energy at frequencies close to the resonances of the duct system.
The adopted methodology is based on a linearized Navier–Stokes solver in the frequency domain with the mean flow field computed via Reynolds-averaged Navier–Stokes (RANS) solutions. The whistling potentiality is investigated via an acoustic energy balance to identify frequency regimes where energy amplification might be present.
The results indicate that although whistling is a nonlinear phenomenon caused by an acoustic-flow instability feedback loop, the linearized Navier–Stokes equations can be used to predict the duct system’s ability to whistle or not.
A large number of applications involve the modeling of ultrasonic wave propagation in fluids and solids. This includes nondestructive testing (NDT), flowmeters, and ultrasound equipment in medical processes. During this session, you will be introduced to strategies for modeling such phenomena in COMSOL Multiphysics®, from the behavior of piezoelectric transducers to the nonlinear propagation of finite-amplitude ultrasonic waves in fluids.
In many cases when defining an acoustics model, you follow some basic guidelines to apply an appropriate mesh based on the physics being modeled. However, in complex systems, when resolving geometries is a determining factor, specific techniques should be used. In this session, you will be introduced to such techniques for the meshing challenges associated with different kinds of acoustics models in complex geometries.
The design and optimization of loudspeakers is a challenging multiphysics problem that requires various numerical approaches, depending on the accuracy required and the complexity of the system. This can range from lumped electroacoustics models in the frequency domain to nonlinear transient analyses of total harmonic distortion. In this session, you will receive insight into the modeling techniques available for loudspeaker simulations as well as appropriate postprocessing tools that provide you with a fully virtual testing environment.
When solving large acoustics models, it can be beneficial to tune the solvers by considering performance, stability, and memory consumption. A good strategy with respect to meshing and other modeling options is also important. This session will illustrate the process, from choosing one of the predefined solver suggestions in COMSOL Multiphysics® as a starting point to determining how the solver settings can be manipulated and tuned for robust modeling of acoustics phenomena.
Noise and vibration analysis covers areas from ground-borne noise and noise generated by machinery to the analysis of feedback in electroacoustics applications. The physics involved in such applications deal with the combined propagation and interaction of elastic waves in structures and pressure waves in fluids. In this session, you will learn how to model these phenomena through several examples and demonstrations.
Sound and audio phenomena covers large ranges in both wave propagation and wavelength. In order to model all acoustics-based applications, the Acoustics Module uses different numerical methods depending on the application or problem at hand. Some methods are coupled implicitly by the numerical algorithm within COMSOL Multiphysics®, such as the finite element method to the boundary element method, while others require a more manual approach, such as coupling the finite element method to ray approximations. This session will introduce the settings, features, and strategies required to apply both methods.
Technology Manager, Acoustics
Senior Developer, Acoustics
Managing Director, Denmark
Lead Applications Engineer