Frequently asked questions

SpectraSim is a Windows desktop application for duct acoustics with flow. It predicts the pressure drop and the acoustic performance — transmission loss, insertion loss and radiated sound — of exhaust mufflers and silencers from one 3-D CAD model, coupling a CFD flow solver with a finite-element acoustic solver in one guided workflow.

SpectraSim calculates transmission loss, insertion loss, radiated SPL (A-weighted) and 1/1 and 1/3 octave bands from finite-element acoustics; total-pressure loss Δp₀, engine back-pressure, loss coefficient ζ and flow split from CFD; and wall heat loss and temperatures from heat transfer.

SpectraSim imports STEP, IGES and STL. Units are always confirmed on import, because CAD files do not reliably carry their unit; models made of several solid bodies are split into their flow regions automatically.

No. The wizard writes, meshes and runs the CFD cases, and OpenFOAM is installed with SpectraSim. Each setting has an F1 theory article with the equation, the default and references.

Yes. Measured curves are imported in the Postprocessing step and overlaid with one or more runs.

No. SpectraSim solves the 3-D geometry, which captures cross-modes, complex internals and temperature gradients that 1-D network models miss. See Acoustics.

Not yet; SpectraSim uses SI units only. An SI / Imperial switch is Planned.

Not yet. Flow-generated noise is not part of this version; it is Planned.

SpectraSim is checked against three kinds of reference: measurements, exact or analytical solutions, and a commercial finite-element code. Against measured transmission loss of concentric-tube resonators, peak levels agree within about 2 dB. Against a commercial finite-element code on a muffler with an extended-tube chamber at 20 °C, the TL rms difference is 0.12 dB. The acceptance criterion against measurement is ±3 dB. Every case, with its reference type and difference, is on the Validation page.

Because a code-to-code comparison shows only that two programs solve the same equations alike; only a measurement shows that both describe the real muffler. SpectraSim therefore states the reference type with every validation number.

An Experimental feature runs, but its results have not been verified against a measurement or a published result yet; treat them as indications, not as numbers to design with. In this version: compressible flow with the transonic SIMPLE and pseudo-transient solvers. The full list is in Known limitations.

No. SpectraSim is simulation software for design work, not a certified test method, and it carries no certification or standards approval. Type approval and noise certification require the measurement the standard prescribes; use SpectraSim to design the muffler and predict its performance before that test.

No. SpectraSim runs on Windows 10 and 11, 64-bit, only.

Never. SpectraSim has no telemetry and no online activation; licences are offline files.

SpectraSim needs 16 GB RAM (recommended; large acoustic sweeps use several GB per worker), about 5 GB of disk for the program and flow solver plus 20 GB or more for runs, and administrator rights once for the installation. Processor: [MISSING M28 — recommended CPU]. See System requirements.

No. 3-D results are shown in SpectraSim; ParaView is optional, for opening the VTK export.

SpectraSim is sold as a perpetual, yearly or monthly licence, and every licence includes every feature. Prices are given on quotation: request a quote with the licence type and the number of seats.

Perpetual, yearly and monthly licences. Every licence includes every feature; a perpetual licence includes 12 months of maintenance, renewable. See Licensing.

Yes, 30 days, requested from inside the program (Help → Request a licence). Solving works fully; result export and reports are locked, and pictures are watermarked "SpectraSim Trial". See Licence activation.

SpectraSim keeps working for 7 days' grace, then runs in explore mode: projects open, every step works, meshes can be made and projects saved; only solving is locked.

No. Floating and network licences are not available. Academic licences: [MISSING M33 — academic licence terms].

A trial licence is bound to the computer it was requested on. Paid licences: [MISSING M38 — machine binding and licence transfer policy].

Yes. If you have no simulation team, our engineers run the study for you: you send the geometry and targets, we simulate acoustics, flow and heat in one model and compare design variants, and you receive the design and a report with TL, IL, back-pressure and recommended changes. Typical turnaround: [MISSING S01 — typical turnaround]. See Engineering services.

No. The program never connects to the internet; your models never leave your computer.

The website stores the fields you submit, in a private inbox, to answer your request. See the privacy notice [MISSING M17 — privacy notice].