Acoustic simulation

Acoustic simulations require specialized capabilities beyond standard finite element (FE) modeling capabilities. Often you need to model things like the air volume and the area where you want to measure acoustic pressures. Simcenter provides the advanced features you need, such as surface wrapping, convex meshing, mesh thickening and the ability to create hybrid (hexa-tetra) meshes, to help you accelerate acoustic meshing processes more than traditional preprocessors. The availability of various material models for both structure and fluid, and the wide variety of structural and acoustic boundary conditions and loads, allows you to efficiently set up your analysis.

The finite element method (FEM) for acoustics analysis is ideal for simulating interior acoustics problems. In addition to FEM being the more efficient method in terms of solution speed, it lets you perform coupled vibro-acoustics analyses that take structural modes and soundproofing materials into consideration. FEM acoustics can be easily used to solve exterior acoustics problems as well, such as for noise radiation analysis for powertrain components like air induction systems, gearboxes, or full electric drive units.

Often used for exterior acoustics problems, the boundary element method (BEM) is ideal for problems involving very complex geometry that may be a challenge to model for the FEM method. The BEM method helps simplify exterior acoustics simulation since only the outer surface mesh of the geometry is needed. This simplifies both the modeling process and reduces the degrees of freedom in the simulation model which will result in easier analysis.

Flow-induced aeroacoustic noise is a significant component of the acoustic signature of a vehicle or other products. Predicting and understanding noise generation mechanisms, localizing sound sources, identifying transmission paths, and predicting system acoustic response are key to good acoustic design. With Simcenter, you can gain a comprehensive understanding of your noise predictions, enabling you to develop effective design countermeasures. This ensures that your products maintain optimal sound quality and a competitive edge in the market.

Example applications include: noise from heating, ventilation and air conditioning (HVAC) and environmental control system (ECS) ducts, train boogies and pantographs, cooling fans, ship and aircraft propellers and more.

Create aero-acoustic sources close to noise-emitting turbulent flows as computed from a CFD solution and compute their acoustic response in the exterior or interior environment. In aero-vibro-acoustic applications, the flow turbulences are introduced possibly both aerodynamic and aero-acoustic pressure on a structure, which responds by vibrating. These vibrations cause acoustic waves to radiate in the surrounding air. For example, you can predict cabin noise inside cars and aircraft due to wind loads acting on the vehicle’s windows and structural body. The pressure loads at the start of these analyses can come from CFD solutions or from a set of so-called Turbulent Boundary Layer models, included in the software.

When the acoustics problems you need to solve involve very large geometries or very high frequencies, then FEM and BEM solutions become too expensive to solve.

Ray Acoustics is used to predict acoustic responses up to very high frequencies and for very large geometries, in both enclosed and unbounded domains. Unlike FEM or BEM acoustic solvers, ray acoustics exploits the fact that at high Helmholtz numbers, sound propagation can be simulated by ray tracing (a technique also used to simulate high frequency electromagnetics and lighting). Therefore it only requires the mesh to correctly represent the topology of the product and not a fine discretization of the domain. As a result, the solution is not bounded by an upper frequency limit or the model size and solving is done orders of magnitude faster as compared to FEM or BEM solutions.

How can you tell what your product really sounds like by looking at charts and graphs from your simulation? You can't. But Simcenter gives you the ability to listen to your product before you build it.

Acoustics auralization immerses you into a virtual acoustic environment where you can
evaluate the acoustic performance of your designs by listening to simulation results rather than only looking at plots and curves. You can create listening scenarios based on simulated or externally recorded sources and simulated transfer functions obtained from either FEM, BEM or ray acoustics solutions. With acoustics auralization, you can visualize the resulting time data, listen to the scenario and make changes to the individual tracks to improve the sound quality of your product. You can additionally quantitatively evaluate the sound quality based on dedicated loudness and sharpness metrics.