Low-noise design of process installations is essential when the installation is located close to urban areas or for example close to living quarters on an offshore platform. TNO has a unique combination of hardware, software tools and experience to analyse noise problems. We identify dominant noise sources and noise transfer paths. This enables us to mitigate noise problems. Both in the design phase and after startup of the system.
Higher production capacity, more compact fluid machinery design, faster moving machinery – these are just a few examples which may lead to noise problems. The consequences of not complying with local or international guidelines for working conditions (noise levels of >80 dB(A)) and environmental legislation (tonal noise emissions, for instance) can be serious. The installation may have to be shut down temporarily or be allowed to operate at only partial capacity. Both cases are likely to result in significant production losses. An acoustic analysis of all noise sources in an installation during the design phase allows noise-prevention or reduction measures to be taken when they are most (cost) effective. However, it is often at the design stage of process installations that noise-related problems tend to be underestimated and not well considered. TNO is your partner to consult you with the optimal low-noise design strategy.
Various types of noise sources may be encountered in process installations. In addition to fluid-machinery related sources (compressors, pumps, turbines, fans) flow-induced noise sources may occur (valves, T-joints, orifices). TNO has a large database and many simulation tools to quantify these different types of noise sources. In general, noise propagates over long distances inside the piping. Prediction of this noise propgation is our core-business. Also other noise transfer paths (e.g. direct radiation from the machinery or mechanical transfer via the structure) may be encountered. The in-line noise levels will be transferred through the piping wall and will be radiated to the surroundings. This may often occur at large distances from the source. Finally, the calculated noise contours will be used for the final evaluation against permitted levels, according to local or international noise legislation.
In practice, noise problems are often encountered after startup of the installation. The most effective noise reduction technique depends strongly on the dominant noise source - noise transfer path combination. TNO consultants have all required safety trainings to evaluate noise levels in the existing process installation, also offshore. In addition to standard noise measurement equipment, we have advanced tools to identify the dominant noise sources and transfer paths (combination of microphones, accelerometers and intensity measurements). This we combinate with our simulation tools, such as SysNoise, VisiSea, GeoNoise, Equip+ and CAA (Computational Aero Acoustics). This approach allows for a robust root-cause analysis and formulation of cost-effective reduction measures. In our experimental facilities, the effectiveness of noise reduction measured can be evaluated in scale-model tests.