Ultraviolet (UV) light is part of the natural light spectrum. At a wavelength of 254 nm (UV-C), the genetic material of viruses is very reliably destroyed. However, possible UV-C air purifiers must be designed in such a way that the radiation is only directed against the viruses and is completely harmless to humans. A further challenge: the air that is sucked in by the cleaners must remain in the device long enough for all viruses to be killed. If it flows back out too soon, viruses remain alive and thus active.
With virtual simulation for air disinfection with UV light
Keeping your distance, observing hygiene, wearing a mask – this basic formula is an important tool in the fight against corona viruses in public. However, the viruses remain a problem especially in closed rooms, where they can spread very easily due to the reduced air circulation. Therefore, many public institutions such as schools additionally rely on ventilation – with moderate success. Scientists from the hygiene institute biotec have found a better solution together with the Heraeus Noblelight business unit: Special air purifiers based on ultraviolet light can kill 99.9 percent of the corona virus in the air.
Precisely fitting UV-C air purifiers thanks to simulation
In order to adapt UV-C air purifiers specifically to these challenges, Heraeus Noblelight first tested its devices in a virtual simulation. By means of ray tracing analysis, it was observed how the UV radiation propagates in the device and whether it enters the room. The experts also simulated the air flow and how droplets and aerosols are distributed in a room. "It is much easier to first model a product in the virtual world than to physically assemble it directly. Thanks to the precise simulation, we saved many production steps and immediately knew what to look out for," explains Larisa von Riewel, the responsible team leader Computer Aided Engineering (CAE).
The simulations were a prerequisite for the development of the Soluva product range from Heraeus: customized UV-C devices for air disinfection as used in a wide variety of areas, such as court buildings, canteens, retail stores, cultural institutions and schools. "Our Air Management Optimized products have an integrated UV-C lamp. They suck in contaminated air and treat it in such a way that it is exposed to as much UV light as possible. The interaction of UV-C and air leads to the destruction of viruses that are removed in aerosols. For optimal and efficient functionality, parameters such as circulation rate, air volume and pressure loss play a decisive role in the disinfection process," says von Riewel.
Airflow simulation shows the paths of aerosols in rooms
Using state-of-the-art technology, the experts at Heraeus can simulate how droplets and aerosols are distributed physical accurately in a room - here, for example, in an office. The simulation also shows how quickly these aerosols are rendered harmless by disinfection with UV-C light.
First solution for buses worldwide
Thanks to the matured simulation technologies Heraeus Noblelight succeeded besides as the first enterprise world-wide to develop under the designation Soluva air a UV C upgrade for buses. This is already tested in real operation in buses in Hanau, Germany. And with success: The air in the vehicles can be disinfected within fewer minutes. After completion of the test, the devices can be used in public transport worldwide without great effort.
With the simulation tools and corresponding devices, Heraeus Noblelight not only supports the containment of the corona virus . The methodology itself is also used by Heraeus customers worldwide, accelerating the development of innovative solutions for a wide range of industries, such as 3D printing and photovoltaics.