Florian Flaig's research work at the Institute of Dynamics and Vibrations (now: Institute for Acoustics and Dynamics) began with the realization that the methods from lubricated friction can also be used for the simulation of adhesive flows and culminated in his successful doctorate. After the presentation and examination on May 29, 2024, the Institute for Acoustics and Dynamics congratulates Mr. Flaig on this achievement.
In his dissertation, Mr. Flaig describes a simulation method for the flow of adhesives in thin gaps. It deals with the fundamental question of how to ensure that there are no air voids and unfilled areas in an adhesive bond, but that the proportion of excess or leaking adhesive is still minimal.
The core statements of Mr. Flaig's work are that the optimal application patterns for bonding two joining surfaces are all variations of a star-shaped basic distribution and that it is actually possible to precisely bond even geometries that appear to be more complex. In addition, Mr. Flaig showed that the application patterns are independent of the viscosity and therefore of the adhesive, and that high compression ratios can counteract the retention of large air bubbles in joints.
These results were obtained as part of a three-year DFG project in collaboration with the Fraunhofer Institute for Manufacturing Technology and Applied Materials Research (IFAM) in Bremen. A simulation program was expanded and modified, which can now not only describe the flow of the adhesive and the force conditions during the pressing together of two joining surfaces, but is also able to calculate the initial application pattern of the adhesive for a desired target geometry by means of backward simulation. Experimental investigations at IFAM enabled the simulations to be compared and the high level of accuracy combined with low calculation times in the range of seconds to minutes to be confirmed.
Mr. Flaig's results can be used not only in industrial applications, but also in the private use of adhesives. For example, for the next private bonding of two paper squares, the adhesive outflow can be minimized by applying the adhesive in the form of a cross with tapered tips.
Once again this year, 22 interested schoolgirls from grades 5 to 11 joined InAD to spend a day as acousticians and dynamicists. Together we had the opportunity to explore the world of acoustics and dynamics with exciting experiments. From eigenmodes that can be visualised on the acoustic plate (see picture), to the vibration of a loudspeaker that we 'slowed down' using a stroboscope, to the excitation of the natural frequency of a singing bowl, we introduced the girls to the fascinating world of physics and showed them how diverse and exciting science can be. The stereomicroscope, which allowed the girls to experience the nature and surface of their own objects, was also of particular interest. We would be delighted if we could inspire some of them to take a further interest in science.
We would like to take this opportunity to thank all the participants, staff and organisers. See you again in 2025.
The 50th Annual Meeting for Acoustics (DAGA24) took place from March 19-21, 2024 at the Congress Centrum (HCC) in Hanover. The President of the German Society for Acoustics, Prof. Sabine C. Langer (InAD), officially opened the event. The DAGA24 was hosted by the LU Hannover.
The Institute of Acoustics and Dynamics was also represented not only with exciting talks, but also with posters: Poster presentations enabled participants to find out about innovative projects and research results and enter into dialog.
A jury consisting of the heads of the DEGA technical committees selected the winners of the DAGA poster awards from the more than 100 poster presentations. We congratulate Juliette Dietrich from the Institute for Acoustics and Dynamics on winning the DAGA Poster Award 2024. On the poster, she presented the results of her master's thesis on the synthesis of dynamic stochastic loads on aircraft structures at the DLR Institute of Lightweight Structures. Congratulations to her!
At this year's Public Authorities Relay Marathon on 5 June, the InAD selection achieved a solid midfield position with a 41st place out of 84. Amongst the selection teams of various police headquarters, tax offices and research institutions, the scientific staff of the Institute and Prof. Müller ran with the team name "Mach/100" with a time of 3:33:34 over 42 km, just missing the self-imposed target of "Mach/100" = 3.43 m/s. The Institute congratulates the relay team on this achievement and thanks them for their sporting presentation.
From 3 to 7 June 2024, the ECCOMAS Congress took place in the beautiful city of Lisbon. The InAD was represented with three presentations:
1. "Surrogate-Based Bayesian Updating of Finite Element Solutions for State Monitoring" by Prof Ulrich Römer
2. "Application of the Fourier generalised Polynomial Chaos Expansion to Model Limit Cycles under Uncertainty" by Lars de Jong
3. "Ensemble Kalman Filtering for Stochastic Phase-field Models of Brittle Fracture" by Lucas Hermann
The conference provided an excellent opportunity to exchange knowledge and network with colleagues from all over the world. In addition to the exciting presentations, we also enjoyed the culinary highlights of the city, especially the delicious pastéis de nata.
On 26 March 2024, Meike Kollmanthaler successfully defended her doctoral thesis entitled „Methode zur systematischen Entwicklung von akustisch effizienten Leichtbau-Fahrzeugstrukturen“. She took us into the conflicting goals of lightweight vehicle construction and acoustics in the vehicle interior. We are delighted that Meike was able to successfully complete this important milestone and wish her all the best for the future.
In November 2023, the winners of the Machine Dynamics Challenge from the summer semester of 2023 were honored by the Institute for Acoustics and Dynamics. In this challenge, students had the opportunity to work on small additional tasks weekly during the semester, which complemented the lecture with varying levels of difficulty.
The winners were awarded 3D-printed trophies themed around the lecture and the institute during an invitation to coffee and cake with Kassandra Kampen, a staff member of the institute. Professor Müller congratulated students Clemens Focke and Florian Borowski on achieving first place in the challenge for their successful completion of the tasks. In second place were students Fynn Luca Lampe and Jacques Meimann, whose award was accepted by their team colleague on their behalf. The third-place was secured by the trio Artjom Vostrukhin, Omar Elbehairy, and Emir Sagdani.
In addition to the trophy presentation and congratulations, discussions about the institute's work and general study planning framed the meeting. "We always welcome inquiries regarding the supervision of student projects, not only within the strict framework of the advertised projects on the website, and we strive to find the most suitable topic together with the students," described Prof. Müller the procedure for upcoming student projects to the bachelor students. Müller emphasized that it was also possible, in connection with the institute's test stands at the location in Schleinitzstraße, to find the right balance between modeling and practical work for each participant, and invited everyone to get to know the work at the institute through an interesting student assistant position.