ILA Berlin Air Show 2018: Fraunhofer IBP is doing research to make flying a healthful, comfortable and sustainable experience
With a volume of 3.7 billion airline passengers worldwide in 2016, civil aviation once more dramatically increased the air passenger figures. According to a study conducted by the German Federal Statistical Office, passenger figures continue to rise every year due to increasing prosperity, attractive tourist destinations, expanding global trade relations and liberal travel regulations. With the aim of transporting all these passengers to their scheduled destinations in a more healthful, comfortable, economic and environmentally friendly way, the Fraunhofer Institute for Building Physics IBP is continuously doing research on improving aircraft. Using several unique test facilities, IBP scientists address issues concerning the cabin indoor climate and the aircraft as an integrated system. Meet Fraunhofer IBP researchers at the ILA Berlin Air show (25 through 29 April 2018) in Hall 2, stand 229, to learn more about IBP test facilities, research projects and solutions.
Bringing Heaven to Earth
Fraunhofer IBP’s unique »Flight Test Facility« (FTF) has been established at IBP’S Holzkirchen branch near Valley south of Munich. An original A310 fuselage segment, with a length of approximately 15 m and enough space to host up to 80 test subjects, is located in a low-pressure chamber. In addition to analysing the cabin climate, the aircraft is also investigated as an integral system; for instance, cockpit, passenger cabin, avionics and cargo compartment are examined under aspects of energy performance and usage requirements.
An essential aim is to reduce the aircraft weight and hence the fuel consumption, while ensuring a comfortable and healthy indoor climate inside the aircraft passenger cabin.
To develop, validate and eventually demonstrate the feasibility and the associated energy management inside the aircraft, Fraunhofer IBP has enhanced the range of its test labs by adding the »Thermal Test Bench« (TTB). This unique thermal test facility provides IBP scientists and their partners from industry with additional opportunities in this field of research. The »Thermal Test Bench« plays an important role in simulating, validating and testing new systems under thermal aspects. Here, an original aircraft fuselage, which is divided into three typical areas (cockpit, cabin and aft section), allows performing a wide range of specific thermal measurements. The fuselage is exchangeable and can be replaced with a helicopter cabin, for instance. The test facility is completed by the »AirCraft Calorimeter« (ACC), which is used to simulate extreme conditions such as »Rapid Decompression« (rapid cabin depressurisation) or a »Thermal Shock« (sudden temperature drop caused by in-flight damage of the cabin structure). In many respects, IBP‘s TTB presents huge advantages: it reduces the number of required actual test flights, which not only helps to save costs, but also saves the environment.
The »Indoor Environment Simulation Suite« (IESS) was developed by Fraunhofer IBP scientists with the aim of performing and validating thermal simulations in an actual aircraft already at an early stage of new technological developments. This modelling approach allows simulating and validating thermal details and transient conditions in a very time and cost-efficient way. This scalable method presents several advantages, including the quick comparison and evaluation of diverse technologies and architectures at the aircraft as well as co-validation in a realistic testing environment.
The aircraft skin is subject to the toughest standards: it has to be very lightweight, it must withstand extreme loads, and it has to ensure excellent thermal insulation of the aircraft cabin. As the load-bearing construction units of the aircraft door form an unfavourable thermal bridge, the indoor climate at the galley/ door area of the airplane is often perceived as thermally uncomfortable. Here, mainly the floor area is too cold, and tangible temperature stratification can be noticed. In the scope of the KASI project (funded by the German Federal Ministry for Economic Affairs and Energy, BMWi) it was investigated how thermal comfort in this area can be improved for both flight attendants and passengers, by making energy-efficient use of waste heat. For this purpose, a separate air pathway is added to transfer the waste heat emitted by cooling devices installed in the galley into this space. Using the FTF test setup and specially developed measurement systems (e.g. »DressMAN«) for measuring the indoor environment of the galley/ door area, IBP experts were able to determine an optimum combination of air volume and air temperature for this air pathway. In a next step, the actual acoustic situation was documented in the IBP acoustics labs. Based on these findings, appropriate measures were derived and a prototype was designed which achieves substantial acoustic improvements. In this way, Fraunhofer IBP developed a functional demonstration sample and design requirements preparing the serialization of the solution.
Indoor Air Quality and Hygiene at the Focus of Science
Repeatedly, health risks associated with so-called »Fume Events« in passenger airplanes have been reported by the media. In case of a »Fume Event«, the passenger cabin supply air may be polluted with e.g. engine oil vapours. In most cases, this incident is due to problems occurring in the bleed air system that supplies fresh air to the cabin in the majority of passenger planes. Air in aircraft is already permanently filtered. Improving recirculated air filtration and the possible future filtration of bleed air is subject of current research projects. For efficiency testing of air purification systems a special filter test stand was set up at IBP premises. The airflows that have been contaminated with chemical and biological substances or even soot particles are then exposed to various filters, catalysts or converters to test their efficiency and quality. Before/ after comparisons are made to determine (and optimize, where necessary) the effectiveness of air purification devices.
Besides air quality, the hygiene of surfaces is also a great challenge, most of all in the sanitary rooms and particularly on long-haul flights. UV light, which is used to inhibit microbial growth on the critical surfaces, is liable to damage the preferred lightweight plastic and accelerate its ageing process. This is why both the light sources and the materials must be closely matched. Easy-to-clean surfaces or, better still, surfaces that minimize the adhesion of contaminants and are easy to maintain, are examples for optimized airplane hygiene proposed by the researchers.
At ILA Berlin, visitors can experience many of these test facilities at first hand by taking a 360-degree trip wearing 3D VR glasses.
Flying in comfort with individually air-conditioned seats
Indoor climate – also in aircraft cabins – is another important priority in the Fraunhofer IBP research activities. Along with nine European partners from the aviation industry, Fraunhofer IBP had initiated the EU-funded project »iSPACE« (innovative Systems for Personalized Aircraft Cabin Environment) with the aim of developing a customized AC system to enable every passenger to individually control her/his ambient temperature. In the scope of this project the scientists developed technologies designed to optimize in-flight comfort: future passengers shall be able to personalize their cabin environment by adjusting temperature and air supply according to their personal needs.
On the basis of the findings of the iSPACE project, the partner company Gentherm developed a business-class concept seat (Aviation Double Seat) with seat ventilation and seat heating. This combination ensures both an optimum temperature of the seat surface and continuous removal of moisture. As a result, the seat surface will remain comfortable and dry, without any physiological risks. The Aviation Double Seat will be presented at the ILA Berlin 2018 Air Show in Hall 2 at the joint Fraunhofer Booth No. 229. It will soon be introduced on the market.