Ysbrant Wijnant came up with the principle of 'noise diffractors' at the University of Twente (UT). How they work is as follows. When sound waves skim over a groove cut into a concrete block lining a busy road, for example, they are pulled into the groove and amplify each other. This phenomenon is known as resonance, and when the resonating waves emerge back from the groove, they obstruct other passing sound waves, which are deflected upwards. As a result, ground-level noise is attenuated, effectively reducing noise pollution for nearby residents. Wijnant's research at UT ultimately resulted in a spin-off, 4Silence, which successfully marketed the principle through a series of diffractor products. On top of that, the company also developed an innovative acoustic measurement device and provided consultancy services for organizations looking to reduce noise and harmful vibrations. Earlier this year, Demcon carved out and acquired the latter two activities, starting Demcon sound solutions along with 4Silence founder and co-shareholder Wijnant. Wijnant is also affiliated with the UT Department of Engineering Fluid Dynamics as a part-time acoustics researcher.
Sound specialist
Demcon sound solutions will primarily perform multiphysics simulation studies in the context of consultancy and product development, examining the acoustic and vibrational properties of all sorts of structures. This means it will be closely aligned with Demcon multiphysics, which offers high-quality simulation services to contribute to the development of innovative products and complex systems. Given this close relationship, Demcon multiphysics managing director Joost Mulder has now taken on the same role at Demcon sound solutions. "We are more than familiar with acoustic studies at Demcon multiphysics, having worked on medical devices in the past. Medical devices are tricky products when it comes to noise control, as noise-producing equipment has to meet strict requirements, while alarms have to be easy to hear. Ysbrand and his team will be a valuable addition to our in-house expertise and will take us to the next level. With sound being a specific niche in the world of multiphysical phenomena, we decided to dedicate an entirely new company to it, starting Demcon sound solutions. With Demcon sound solutions, Demcon has become a true acoustic specialist with a unique proprietary competence.
Solving noise issues together
Together, the two Demcon companies cover a wide range of markets and application areas, Mulder continues. "Whether you are looking at a high-tech device or a shaky bridge, the underlying physical phenomena are the same. Then again, noise issues can also be caused by other physical phenomena, such as fluid flows or thermal effects. By banding together, we can solve even the most challenging problems in this field, such as the major disruptions that vibrations can cause in high-tech systems. Ideally, one would prevent vibrations by design." Wijnant: "That is one of the topics I am working on at the university, along with a young researcher investigating intra-machine acoustics."
Unique acoustic measurement device
The other branch of Demcon sound solutions is dedicated to Sonocat, a unique acoustic measurement device that Wijnant has now brought to Demcon. The Sonocat is a small sphere equipped with eight microphones that uses its ingenious design and special processing software to tell what direction a particular sound came from. Additionally, the Sonocat can also distinguish incident sound waves from those reflected by a barrier, making it possible to deduce the actual effectiveness of the barrier: the less sound is reflected, the more has been absorbed by the barrier. Conventional acoustic measurement devices only measure total noise intensity and simply cannot provide all the information the Sonocat can.
Complex algorithm
The Sonocat comes with a truly high-tech algorithm, Wijnant explains: "This is not your average math. Moreover, we are now also developing an algorithm for long-distance noise propagation, e.g. for wind turbines or aircraft. Performing accurate acoustic calculations at long distances is a nightmare: you have to factor in lots of approximations and use tons of formulas that often end up being wrong. Just look at Schiphol Airport and the debate on the discrepancy between noise perception and actual noise values. That is exactly the kind of challenge I like to work on."
Focus on technology
Wijnant is delighted with all the new opportunities for implementing his invention and the latitude Demcon has given him to focus on the technology. "At 4Silence, I would find myself selling the Sonocat to a large German firm one day and discussing the particularities of diffractors with a Dutch municipality the next. Fortunately, that time is behind us now and we can focus solely on the engineering. In that respect, being part of the Demcon umbrella has been a real blessing. They can provide commercial support and lend a helping hand with development."
Unparalleled synergies
Demcon's main strength is that it has consolidated many different engineering disciplines, Mulder explains. "They can all contribute to the further development of the Sonocat in one way or another. Besides, our vast number of in-house specialties will also come in handy for our noise consultancy services. We have the capabilities to design and engineer products with excellent acoustic performance for our customers and can even prototype them ourselves. In the world of acoustics, this level of synergy is very rare indeed. My ambition is to be the largest provider of acoustic consultancy services in the Netherlands or even Europe."
Scaling the acoustic summit
Wijnant adds: "My goal is to put this company in a prime position to grow into the field of acoustics and vibrations. With legislation becoming ever more stringent, noise has emerged as a key issue, and in the quest to make quieter products, companies are finding themselves at a loss. Lots of the techniques and technologies involved are non-standard and have to be tailored to a particular situation. No matter how you look at it, it is a tough nut to crack. Fortunately, we are here to help. Our goal is to scale the summit of the field of acoustics and push its boundaries.
About Demcon sound solutions
This young company develops innovative acoustic measurement solutions and works on combating noise and harmful vibrations. The company helps public bodies and industry organizations solve noise-related problems through consultancy services, simulation studies and engineering. Traffic noise and overly noisy machines and devices, for example, are common problems, but so are vibrations, especially in bridges and high-tech machines, where they can disrupt accuracy levels. Demcon sound solutions is part of the international Demcon group and works for fellow Demcon companies and external customers. It works closely with Demcon multiphysics, which offers high-quality simulation services to contribute to the development of innovative products and complex systems.
Demcon (1,100+ employees) develops, manufactures, and delivers technology and innovative products. The Demcon group has multiple branches in the Netherlands, Germany, Japan and Singapore. The company was born out of its founders’ passion for combining creativity and technical skills to solve complex technological and social issues. On top of that, Demcon is committed to fostering entrepreneurship and investing in talent and education.