The consideration of acoustics and aeraulics in a construction project is necessary in relation to different works trades: architectural, technical, not to mention the envelope.

With regard to related issues, SILDIS® software makes it possible to easily, quickly, and reliably perform Computer Aided Design tasks.

All calculations are possible taking into account contextualized thermodynamic conditions:

  • for ambient air (e.g. for ordinary applications in the building sector with the exception of those related to exhaust gases, involving high temperatures, for which calculations are also possible)
  • as required for simulations in the context of industrial construction projects (possibly with fluids other than air and extreme conditions)

In terms of acoustics, the frequency range considered for single frequency simulations is 20 Hz - 20 kHz, the performance indicators being provided in bands of 1/3 octave, 1/1 octave and in the form of a unique index with respect to a reference sound spectrum (e.g. αw, Rw).

The fact that the software is in Excel format, with drop-down menus and with the possibility of selecting materials from libraries [1] makes it a practical tool for various participants in the construction process: project managers, architects, consultants, technicians and engineers from design offices (acousticians, specialists in aeraulics and fluids) and manufacturers Research and Development (R&D) centers.

Sound transmission through partitions

The software allows the prediction of the sound reduction index of walls, possibly multilayered, for sound insulation:

    • constituting the envelope of buildings: walls, slabs, roofs or subject to interior carpentry work (e.g. metal or wood joinery) and plastering: partitions, ceilings, linings, not to mention industrial acoustic insulation panels, screens (noise barriers) and also components of glass doors and frames
    • constituting the envelope of silencers inserted in ventilation and air conditioning networks or in chimneys

Calculations are possible by combining plates (e.g. concrete, plaster, wood, steel, aluminum, glass) [2], possibly joined together, and porous materials (glass wool, rock wool, basalt wool polyester or ceramic fiber based wool, foams) [3].

The plates can be plane, orthotropic (i.e. with corrugations), perforated, with or without a bonded viscoelastic damping layer (e.g. septum, PVB): extensional or constrained (between 2 plates: sandwich panels).

The results of the calculations are comparable to the standard measurement: cf. NF EN ISO 140-3 Acoustics - Measurement of sound insulation in buildings and of building elements - Part 3: laboratory measurement of airborne sound insulation of building elements.

links toward other pages of this site : modules of software SILDIS®

links toward other pages of this site : R&D blog archives

>> Improvement of the way for taking into account the interactions between porous media for the design of multilayered acoustic structures with the simulation software SILDIS®

>> Integration of the computation of the acoustic performance of rectangular ducts and of circular ducts walls to the simulation software SILDIS®

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Sound absorption

The software allows the prediction of the sound absorption coefficient of linings, possibly multilayered, for the limitation of the reverberation of premises:

    • constituting ceiling tiles and suspended baffles, wall panels, laggings, not to mention industrial sound insulation panels, screens (noise barriers) and dividers

Calculations are possible by combining plates (e.g. plaster, wood, steel, aluminum) [4] possibly perforated, porous materials (glass wool, rock wool, basalt wool, polyester ceramic fibers based wool, foams) [3] and facings (cloths, fabrics) [5]

The results of the calculations are comparable to the standard measurement: cf. NF EN ISO 354 Acoustics - Measurement of sound absorption in a reverberation room and also standard ISO 10534-1 Acoustics - Determination of the sound absorption coefficient and impedance in impedance tubes - Part 1: Method using standing wave ratio.

links toward other pages of this site : modules of software SILDIS®

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>> Acoustics – Design and sizing of plate resonators with circular, square or slotted perforations or not perforated (for silencers and absorbing linings) with software SILDIS®

>> Improvement of the way for taking into account the interactions between porous media for the design of multilayered acoustic structures with the simulation software SILDIS®

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Limitation of noise transmission in ducts

The software allows the prediction of the insertion loss, of the self noise and of the total pressure loss of elements of aeraulic networks whose impact, in the event of accumulation, is calculated:

    • silencers [6], either resonant or dissipative (i.e. with absorbent lining, possibly multilayered). The calculations are possible by combining plates (e.g. steel, aluminum) [4] possibly perforated, porous materials (glass wool, rock wool, basalt wool, polyester or based on ceramic fibers wools, foams) [3] and facings (cloths, fabrics) [5]
    • straight lengths, elbows, nozzles

The components of the air network can be of rectangular or circular cross section.

For a rectangular silencer, the results of the calculations are comparable with the standardized measurement: see NF EN ISO 7235 Acoustics - Laboratory measurement procedures for silencers in ducts and terminal units - Insertion loss, flow noise and total pressure loss.

links toward other pages of this site : modules of software SILDIS®

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>> Acoustics – Design and sizing of plate resonators with circular, square or slotted perforations (for silencers and absorbing linings) with software SILDIS®

>> Acoustics - simulation software SILDIS® – silencers sizing online

>> Silencers - new sizing possibilities for acoustics and aeraulics : ITS is looking for an industrial & commercial partner

>> Improvement of the prediction of the acoustic and aeraulic performance of cylindrical silencers (with central pod)

>> Silencers - Modeling the acoustic behavior of curved absorbers

>> Sizing of reactive silencers with non-perforated tubes with the simulation software SILDIS®

>> Integration of the prediction of piping systems discharge parameters to the simulation software SILDIS®

>> Integration to the simulation software SILDIS® of the calculation of flow indicators for the prediction of industrial processes control valves aerodynamic noise

>> Integration of the prediction of industrial processes control valves aerodynamic noise to the simulation software SILDIS®

>> Integration of the sizing of silencers made of discontinued splitters (baffles) to the simulation software SILDIS®

>> Integration of the prediction of the acoustic performance of nozzles to the simulation software SILDIS®

>> Integration of the prediction of the acoustic performance of bends to the simulation software SILDIS®

>> Integration of the prediction of the sound power radiated by the casing of components of duct systems to the simulation software SILDIS®

>> Integration of the prediction of the acoustic performance of straight ducts to the simulation software SILDIS®

>> Integration of the sizing of rectangular silencers made of splitters (baffles) with a low total pressure loss to the simulation software SILDIS®

>> Improvement of the way for taking into account the interactions between porous media for the design of multilayered acoustic structures with the simulation software SILDIS®

>> Integration of the computation of the acoustic performance of rectangular ducts and of circular ducts walls to the simulation software SILDIS®

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Sound propagation inside rooms

The software allows the prediction of the reverberation time and the sound spatial decay in rooms, for acoustic comfort and noise limitation.

The results of the calculations are comparable with standardized measurement: NF EN ISO 3382-2 Acoustics -Measurement of room acoustics parameters- Part 2: reverberation time in ordinary rooms and NF EN ISO 3382-3 Acoustics -Measurement of room acoustics parameters- Part 3: Open plan offices.

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>> Integration of the prediction of the spatial decay of speech in open spaces to the simulation software SILDIS®

>> Integration of the prediction of sound decay in enclosed spaces to the simulation software SILDIS®

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Sound transmission outside of buildings

The software allows the prediction of sound pressure levels at specified locations.

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Sound propagation outdoor

The software allows the prediction of atmospheric sound absorption, of stacks directivity.

Some of the calculation results are comparable with some input data envisaged in standardized calculation: cf. NF EN ISO 9613-2 Acoustics -- Attenuation of sound during propagation outdoors -- Part 2: General method of calculation

links toward other pages of this site : modules of software SILDIS®

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Overall, regarding simulations for acoustics and aeraulics in the construction sector

In the matter of Computer Aided Design (CAD): SILDIS® calculation software for acoustics and aeraulics in the construction sector (in Excel format) is a versatile tool, marketed (with associated training) by Isolation Technologie Services (ITS) in the form of modules, some of which are grouped in packs, according to the needs of users (interface available in French or in English)

The software output data, in terms of simulation of the sound transmission through walls, of sound absorption, of the limitation of noise transmission in ducts, of sound propagation inside rooms and outdoor are useful for many projects, allowing sizing and technical optimization of various construction products and systems, in relation to issues being acoustic comfort and / or soundproofing.

toward other pages of this site : general information on software SILDIS®

>> Acoustics simulation software SILDIS®

>> Acoustics calculation software SILDIS®

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>>  Practices, evolutions and trends for acoustical design in the construction sector, in relation to the developments of Computer Aided Design (CAD)

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[1] the specific characteristics of the materials to be taken into account for the calculations - in addition to the thickness and number of layers, as well as their stacking order - are tabulated

[2] the specific characteristics taken into account are the Young's Modulus, the density, the Poisson factor, the loss coefficient

[3] the specific characteristics taken into account are the resistivity, the porosity, the tortuosity, the thermal characteristic length, the viscous characteristic length, the density

[4] the specific characteristics taken into account are the Young's Modulus, the density, the Poisson factor, the loss coefficient, the installation conditions (free or embedded), and, in the case of perforated plates: the porosity, the geometry of the perforations

[5] the specific characteristics taken into account are the resistance to air flow, the surface mass

[6] the specific characteristics taken into account are the flow rate, the dimensional parameters (e.g. geometry of the internal parts, length)