Mesh Workflow: Meshing Without Geometry Preparation

Speaker enclosure with an overlaid finite element mesh of the acoustic domain | © CADFEM / Adobe Stock

Why Does Acoustics Need a Dedicated Mesh Workflow?

For acoustic, CFD, or CHT analyses, the component itself is not the analysis domain – the surrounding air volume is. Building that as clean geometry is time-consuming, especially when components have gaps, voids, or penetrations. The Mesh Workflow solves exactly this: the starting point is the existing structural geometry alone – no prepared air volume, no detour via CAD cleanup or Shared Topology.

The following video shows the workflow applied to the structural geometry of a loudspeaker box – nothing more is needed as a starting point. The goal is to analyze sound radiation as a frequency response at a virtual microphone in the far field. What stands out: three guided decisions are sufficient to generate the FEM mesh of the acoustic domain. Reviewing and adjusting predefined settings remains possible at any time and is straightforward. With the classical approach, the same decisions are required – but only after CAD cleanup, negative volume creation and Shared Topology – steps whose effort is model-dependent and therefore virtually impossible to schedule.

Acoustic Mesh Workflow for a Loudspeaker Enclosure: The only starting point is the CAD model of the enclosure itself - the FEM mesh for the acoustic domain is generated based on three guided decisions. | © CADFEM Germany GmbH

How Do I Start the Mesh Workflow in Ansys Mechanical?

Getting started is straightforward: a right-click (RMB) on the Mesh object in the outline tree is all it takes to insert a Mesh Workflow. Ansys provides predefined workflows depending on the analysis type – for acoustics, electronics, or custom tasks via the Custom Mesh Workflow.

Inserting a Mesh Workflow via right-click on the Mesh object. | © CADFEM / ID: MR03NN

Once the workflow is inserted, the Control Panel opens – the central input assistant for all required parameters. It guides the user step by step through the necessary inputs and indicates contextually which data is needed next. The Control Panel presents exactly the three decisions required for the Acoustic Mesh Workflow: frequency range, openings to be closed, and the material point for the interior domain. No further input is required – everything else is handled by the workflow itself. Fine-tuning the mesh generation settings globally and locally remains possible at any time.

The Control Panel guides through the required inputs – shown here for the Acoustic Mesh Workflow. | © CADFEM / ID: F2MAQA

Which Steps Generate the Finished Mesh?

The source geometry itself is not meshed directly. Instead, a wrapping process encloses it with a closed surface representing the inner boundary of the air domain. Gaps and voids are bridged by the wrapper automatically. Between this surface and a provided outer enclosure, the air volume is generated as a mesh – directly, without any geometry creation. On the outside, an IPML region (Irregular Perfectly Matched Layers) is prepared as a Named Selection within the Mesh Workflow. During the subsequent analysis setup, this region is populated with IPML elements, which act as a non-reflecting boundary condition. This ensures that sound radiates cleanly into the far field across the boundary surface and is not reflected back unphysically, as would otherwise be the case.

Outline tree with Input, Steps and Output – the loudspeaker box geometry (4 parts) serves as the starting point. | © CADFEM / ID: BNZWQR

Once the Mesh Workflow is inserted, the outline tree displays three basic steps. As Input, the starting geometry is passed in and converted into a faceted topology during the initialization step – on this basis, the PrimeMesh kernel meshes the model. Under Steps, predefined workflows already contain the sequence: global and local mesh size, surface mesh, optional wrapper, then volume mesh or shell model. For the acoustic model, an additional enclosure body is integrated, which forms the air volume together with the meshed surface.

The seven predefined Steps of the Acoustic Mesh Workflow – the result: loudspeaker box with fully meshed air volume "Air" listed under Geometry. | © CADFEM / ID: HKGZFI

In the Output step, Complete Workflow defines which meshed topology is transferred back into the simulation – available as new geometry directly under the Geometry object. As the resulting mesh illustrates, the same workflow addresses both classical acoustic problems: while section 1 shows sound radiation into the free field (exterior problem, surrounding air volume), the image here shows the interior problem: the air volume inside the loudspeaker box itself, meshed for example for an acoustic modal analysis to determine the cavity resonances of the box.

"Complete Workflow" transfers the generated mesh back into Ansys Mechanical – as meshed geometry ready for further simulation. | © CADFEM / ID: 2C2CUL

When Does the Stacker Mesh Workflow Pay Off?

Layered structures such as printed circuit boards (PCBs) pose a fundamental challenge for classical meshing: every layer, every through-hole, every component would need to be individually prepared and connected as geometry – a Sisyphean task for real-world components.

The Stacker Mesh Workflow approaches this from a different angle: the entire structure is projected onto a single plane and meshed there as a unified 2D topology covering all layers. This mesh is then extruded normal to the PCB surface through all layers. What would be nearly impossible to resolve at the geometry level is handled automatically by the workflow.

With the Stacker Mesh Workflow – the complex layered structure with all through-holes as an extruded volume mesh. | © CADFEM / ID: AEU648

What Can the Custom Mesh Workflow Do – and for Whom?

Anyone facing a meshing task that does not match any predefined workflow turns to the Custom Mesh Workflow. Custom sequences can be freely assembled – based on a geometry, but also starting from an existing mesh. Assignments are made via Named Selections or body names in the Control Panel; with consistent naming, the workflow becomes a reusable template. A typical use case is shell models made up of surface bodies that touch but share no common geometry – the workflow meshes them with shell elements and connects them at mesh level. Geometry-based connections and contacts are no longer required.

Custom Mesh Workflow for connecting and meshing independent surface bodies – connected at mesh level without shared geometry. | © CADFEM / ID: RUSKXA

A second example demonstrates how powerful the template principle is in practice: bolts are regularly meshed in simulation models as axisymmetric solid bodies – an optimal approach, but only if the settings are known and re-applied every time. Once a specialist stores these settings in the Custom Mesh Workflow, an inexperienced colleague can apply the template directly – export and import via the context menu, with all individual steps remaining visible and adjustable at any time.

Bolt meshed using the axisymmetric method – stored as a template in the Custom Mesh Workflow and ready for reuse. | © CADFEM / ID: A1BVPI

Once something works as a template, it can be shared in a targeted way via the Mesh Workflows tab in the ribbon using export and import – with colleagues, teams, or as part of a standardized process chain. All steps remain fully visible and adjustable after import, making the workflow robust in practice. Those who want to explore design variants without geometry parametrization will find a dedicated workflow in Direct Morphing – which we will not cover further here.

Export and import of a Mesh Workflow via the context menu. | © CADFEM / ID: L789FG

Conclusion

With the Mesh Workflow, meshing decouples from geometry – and this fundamentally changes the modeling logic. Anyone who previously needed to build an analysis domain for acoustics, fluid, or heat transfer had to first create the geometry of the air volume, ensure geometrically conforming interfaces, and only then mesh. The Mesh Workflow reverses this: the mesh is generated directly from the boundary mesh – without prior geometry creation, without the constraint of Shared Topology.

Particularly valuable is the ability to save a configured Mesh Workflow as a template and share it with others. Experienced users store their meshing strategy once – less experienced colleagues apply the template directly, without needing to understand the underlying details. The frequently asked question "Can't I just reuse my settings?" is finally answered clearly by the Mesh Workflow: yes.

Furthermore, the Mesh Workflow enables the export and import of meshes for reuse in new simulation models – a capability that did not previously exist in Ansys Mechanical. Combined with the predefined workflows for acoustics, electronics, and structural assemblies, as well as the Custom Mesh Workflow as an open platform, a new level of freedom in model creation emerges – one that goes far beyond meshing itself.

Do you already have a meshing task in mind? The matching Let's Simulate is now available on the CADFEM learning platform – and if it was the acoustics that caught your attention while reading, you will find the next step under "Simulation of Sound Propagation in Acoustics".