Flow Acoustics Laboratory Göttingen (SAG)

Mobile system for acoustic measurement techniques

Based at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) DLR Institute of Aerodynamics and Flow Technology in Göttingen, this mobile large-scale facility can be used in a variety of systems, in particular in wind tunnels and in flight tests. It enables the complex measurement of sound pressure, sound velocity and structure-borne noise on surfaces on Earth or in space. The hardware and software are available for industrial projects, but the scientific knowledge gained from the facility is also very important for internal DLR projects.

Globally unique possibilities for aeroacoustic measurements

The DLR large-scale facility serves to provide and further develop acoustic and aeroacoustic measurement technology for research projects. One of the key areas of focus for those working at the Flow Acoustics Laboratory Göttingen (SAG) facility is the development of microphone-array hardware and the corresponding SAG-AS software for conducting measurements in open or closed test sections or during flight tests. The ability of such instrumentation to identify and locate sound sources within a volume with high spatial resolution is a focal point of the work at SAG. A typical application is the use of microphone arrays to measure the position and strength of sound sources emanating from an aircraft model in a wind tunnel airflow.

One globally unique feature of the measurement equipment is the possibility to perform aeroacoustic measurements on scaled models at flight-representative Reynolds numbers in cryogenic and pressurised wind tunnels (European Transonic Windtunnel [ETW], Cryogenic Wind Tunnel Cologne [CWTC]). In Europe, only a few wind tunnels and research institutions have comparable measurement technology (Aircraft Research Association [ARA], German-Dutch Wind Tunnels [DNW], the French Aerospace Lab [ONERA]). The possibility of using such technology flexibly in different wind tunnels makes this equipment unique and promotes the use of sound-measuring instrumentation in industrial wind tunnels in Germany (ETW, DNW, Bremen Low Speed Wind Tunnel [BLSWT], CWTC) and the rest of Europe (Large Low-speed Facility [DNW-LLF] and RUAG). Being able to support project initiation is also a key benefit, especially as part of the Aviation Research Programme launched by the Federal Ministry for Economic Affairs and Climate Action (BMWK) or initiatives by the European Union.

Only with this large-scale facility is it possible to fulfil third party-funded contracts (for example, for Airbus in the aviation industry, and VW, Daimler, Porsche and Audi in the automotive sector). The facility also allows DLR to meet its commitments within the Aviation Research Programme and the Clean Sky 2 programme. Furthermore, the Flow Acoustics Laboratory helps to maintain and build on partnerships both within Germany (university education and bachelor's, master’s and doctoral programmes) and international collaborative efforts (for example with Trinity College in Dublin, ONERA, NASA, the Korea Railroad Research Institute [KRRI] and the Railway Technical Research Institute [RTRI]). In addition, the facility provides DLR with unique capabilities compared with its counterparts in the UK, France and the USA.


Volker Speelmann

Head of Research Infrastructures
German Aerospace Center (DLR)
Executive Board department for Innovation, Transfer and Research Infrastructure
Linder Höhe, 51147 Cologne

Dr.-Ing. Carsten Spehr

German Aerospace Center (DLR)
Institute of Aerodynamics and Flow Technology
Experimental Methods
Bunsenstraße 10, 37073 Göttingen