With the expert system Option SET (Sound Emission and Transmission), challenges of modeling sound sources are simplified considerably while retaining complex arrangements of sound sources. Sound power spectra can be automatically generated based on technical system parameters of a sound source (for example electric power in kW, volume flow in m³/h, rotations in 1/min etc.), thus a unique system capable of modeling various kinds of sound sources is achieved. Option SET comes with about 150 predefined modules for technical sound sources such as electric and combustion engines, pumps, ventilators, cooling towers, gear boxes etc. The range of sources and systems can be extended by the user. The sound power spectra calculated with Option SET can be addressed to point, line or areas sources after having specified their respective technical parameters. With Option SET, you can not only model the sound radiation from an individual sound source, but you can also model the sound transmission in a chain of sources (e.g. ventilator with complete duct system). Furthermore, based on the predefined modules, you can model even more complex sound source configurations describing the sound radiation of an entire technical component (e.g. cooling tower).
In an example shown in Figure 1, multiple industrial sources are modeled using CadnaA’s Option SET. A fan and a pressure pipe are modeled along a facade of a building utilizing the “edit facade” feature released with the latest CadnaA v4.3 (Figure 2). The Power Level of the fan is modeled as a point source using flow rate and total pressure difference parameters. The parameters for one of the pressure pipes modeled as a line source are shown in Figure 3. Additionally, the radiating noise from the stack visible in Figures 1 and 2 is modeled as a vertical line source with its parameters such as chimney diameter and exhaust temperature shown in Figure 4. Finally, the chimney opening on top of the stack is modeled as a point source with parameters set for the cross sectional surface and radiation angle in steradian units. Once all the technical parameters for each sound source are specified, CadnaA calculates the sound power spectra levels while simplifying the modeling process for the user. The levels can thus be used in predicting the sound propagation in the entire model. For additional information on Option SET, visit the DataKustik website by clicking here.