Johann Groß

Articles published in peer-reviewed journals

1. Gross, J.; Gupta, V.; Berthold, C.; Krack, M.: A new paradigm for multi-fidelity continuation using parallel model refinement. Computer Methods in Applied Mechanics and Engineering, 2024. doi: 10.1016/j.cma.2024.116860
2. Schwarz, S.; Reil, J.; Gross, J.; Hartung, A.; Rittinger, D.; Krack, M.: Friction Saturated Limit Cycle Oscillations - Test Rig Design and Validation of Numerical Prediction Methods. J. Eng. Gas Turbines Power, 2023. doi: 10.1115/1.4063769
3. Ferhatoglu, E.; Groß, J.; Krack, M.: Frequency response variability in friction-damped structures due to non-unique residual tractions: Obtaining conservative bounds using a nonlinear-mode-based approach. Mechanical Systems and Signal Processing, 2023. doi: 10.1016/j.ymssp.2023.110651
4. Berthold , C.; Gross, J.; Frey, C.; Krack, M.: Fully Coupled Numerical Analysis of Flutter Induced Limit Cycle Oscillations: Frequency Versus Time Domain Methods. Accepted in Journal of Engineering for Gas Turbines and Power
5. Gehr, F.; Theurich, T.; Monjaraz-Tec, C.; Gross, J.; Schwarz, S.; Hartung, A.; Krack, M.: Computational and experimental analysis of the impact of a sphere on a beam and the resulting modal energy distribution. Mechanical Systems and Signal Processing, 180, 109407, 2022, doi: https://doi.org/10.1016/j.ymssp.2022.109407
6. Monjaraz-Tec C.; Kohlmann L.; Schwarz S.; Hartung A., Gross j.; Krack M.: Prediction and validation of the strongly modulated forced response of two beams undergoing frictional impacts. Mechanical Systems and Signal Processing, 180, 109410, 2022, doi: https://doi.org/10.1016/j.ymssp.2022.109410
7. Müller, F.; Woiwode, L.; Gross. ; Scheel, M.; Krack, M.: Nonlinear Modal Testing using Base Excitation. Mechanical Systems and Signal Processing, 177, 109170, 2022, doi: https://doi.org/10.1016/j.ymssp.2022.109170
8. Woiwode, L.; Müller, F.; Gross, J.; Scheel, M.; Krack, M.: How Intrusive Are Accelerometers for Measuring Nonlinear Vibrations? A Case Study on a Compressor Blade Subjected to Vibro-Impact Dynamics? Journal of Vibration and Acoustics 144(4), 2022 . doi: 10.1115/1.4053357
9. Berthold, C.; Gross, J.; Frey, C.; Krack, M.: Development of a fully-coupled harmonic balance method and a refined energy method for the computation of flutter-induced Limit Cycle Oscillations of bladed disks with nonlinear friction contacts. Journal of Fluids and Structures (102), 2021. doi: 10.1016/j.jfluidstructs.2021.103233
10. Monjaraz, C.; Gross, J.; Krack, M.: A massless boundary component mode synthesis method for elastodynamic contact problems. Journal of Computers and Structures.
11. Gross, J.; Krack, M.: Multi-Wave Flutter Vibrations in Mistuned Cascades With Tip-Shroud Friction. Journal of Engineering for Gas Turbines and Power, Mar 2021, 143(5), doi: 10.1115/1.4047889.
12. Gastaldi, C.; Gross, J; Scheel, M.; Berutti, T.M.; Krack, M.: Modeling Complex Contact Conditions and Their Effect on Blade Dynamics. Journal of Engineering for Gas Turbines and Power, Dec 2020, 143(1), doi: 10.1115/1.4049186.
13. Woiwode, L.; Gross, Krack, M.: Effect of Modal Interactions on Friction-Damped Self-Excited Vibrations. Journal of Vibration and Acoustics, Oct 2020, 143(3), doi: 10.1115/1.4048396.
14. Berthold, C.; Gross, J.; Frey, C.; Krack, M.: Analysis of Friction-Saturated Flutter Vibrations With a Fully-Coupled Frequency Domain Method. Journal of Engineering for Gas Turbines and Power, Oct 2020, 142(11), doi: 10.1115/1.4048650.
15. Berthold, C.; Gross, J.; Frey, C.; Krack, M.: Numerical Investigation of Flutter Vibrations of Shrouded Turbine Blades with Fully –C oupled Nonlinear Frequency Domain Methods. Journal of Fluids and Structures.
16. Lacayo, R.; Pesaresi, L.; Gross, J.; Fochler, D.; Armand, J.; Salles, L.; Schwingshackl, C.W.; Allen, M.; Brake, M.R.W.: Nonlinear modeling of structures with bolted joints: A comparison of two approaches based on a time-domain and frequency-domain solver, Mechanical Systems and Signal Processing 114, 413-438, 2019, doi: 10.1016/j.ymssp.2018.05.033
17. Schwarz, S.; Kohlmann, L.; Hartung A.; Gross, J.; Scheel, M.; Krack, M.: Validation of a turbine blade component test with frictional contacts by phase-locked-loop and force-controlled measurements, J. Eng. Gas Turbines Power, 2018. doi: 10.1115/1.4044772
18. Gross, J.; Krack, M.: Multi-Wave Vibrations caused by Flutter Instability and Nonlinear Tip Shroud Friction, J. Eng. Gas Turbines Power, 2018. 1115/1.4044884
19. Theurich, T.; Gross, J.; Krack, M.: Effects of modal energy scattering and friction on the resonance mitigation with an impact absorber. Journal of Sound and Vibration 442, 71-89, 2019. doi: 10.1016/j.jsv.2018.10.055
20. Hartung, A.; Hackenberg, H.-P.; Krack, M.; Gross, J.; Heinze, T.; Panning-von Scheidt, L.: Rig and Engine Validation of the Nonlinear Forced Response Analysis Performed by the Tool OrAgL. Eng. Gas Turbines Power 141(2), 9pp, 2018. doi: 10.1115/1.4041160
21. Gross, J.; Buhl, P.; Weber, U.; Schuler, X.; Krack, M.: Effect of creep on the nonlinear vibration characteristics of blades with interlocked shrouds. International Journal of Non-Linear Mechanics 99, 240-246, 2018. doi: 10.1016/j.ijnonlinmec.2017.12.002
22. Gross, J.; Schoenenborn, H.; Krack, M.: Analysis of the effect of multi-row and multi-passage aerodynamic interaction on the forced response variation in a compressor configuration – part 2: effects of additional structural mistuning. J. Eng. Gas Turbines Power 140(5), 9pp, 2018. doi: 10.1115/1.4038869

Book Chapter

1. Gross, J.; Brake, M.R.W.: A Standard Practice for Modeling Bolted Joints in a Finite Element Package, The Mechanics of Jointed Structures (2018), Brake, Matthew R.W. (Ed.), ISBN: 978-3-319-56818-8.
2. Brake, M.R.W.; Gross, J.; Lacayo, R.M.; Salles, L.; Schwingshackl, C.W.; Reuss, P.; Armand, J.: Reduced Order Modeling of Nonlinear Structures with Frictional Interfaces, The Mechanics of Jointed Structures (2018), Brake, Matthew R.W. (Ed.), ISBN: 978-3-319-56818-8.

Book

1. Krack, M; Gross, J.: Harmonic Balance for Nonlinear Vibration Problems . Springer, Mathematical Engineering Series (2019), 160 pages, ISBN: 978-3-030-14022-9, doi: 1007/978-3-030-14023-6

Software

1. NLvib (ila.uni-stuttgart.de/nlvib/): An open source MATLAB tool for computational nonlinear vibration analysis    (Harmonic Balance, shooting method, path continuation, nonlinear modal analysis, etc.)
2. PEACE: An open source MATLAB tool for parallelized model refinement and multi-fidelity continuation. The theory behind the method and numerical examples are presented in [doi: 10.1016/j.cma.2024.116860].

Conference Papers

1. Dreher, T.; Balaji, N.N.; Gross, J.; Brake, M.R.W.; Krack, M.: Gerrymandering for Interfaces: Modeling the Mechanics of Jointed Structures. In: Kerschen G., Brake M.R.W., Renson L. (eds) Nonlinear Structures and Systems, Volume 1. Conference Proceedings of the Society for Experimental Mechanics Series (2020). Springer, Cham, doi: 10.1007/978-3-030-12391-8
2. J.; Armand. J.; Lacayo, R.M.; Reuss, P.; Salles, L.; Schwingshackl, C.W.; Brake, M.R.W.; Kuether, R.J.: A Numerical Round Robin for the Prediction of the Dynamics of Jointed Structures. In: Allen M., Mayes R., Rixen D. (eds) Dynamics of Coupled Structures, Volume 4. Conference Proceedings of the Society for Experimental Mechanics Series (2016). Springer, Cham, doi: 10.1007/978-3-319-29763-7_10
3. Gross, J; Seeger, B.; Peter S.; Reuss, P.: Applying the Transmission Simulator Techniques to the Ampair 600 Wind Turbine Testbed. In: Allen M., Mayes R., Rixen D. (eds) Dynamics of Coupled Structures, Volume 4. Conference Proceedings of the Society for Experimental Mechanics Series (2016). Springer, Cham, doi: 10.1007/978-3-319-29763-7_20
4. Schreyer F.; Gross J.; Reuss P.; Junge M.; Schoenenborn H.: Consideration of Interface Damping in Shrouded Mistuned Turbine Blades. In: Allen M., Mayes R., Rixen D. (eds) Dynamics of Coupled Structures, Volume 1. Conference Proceedings of the Society for Experimental Mechanics Series (2014). Springer, Cham, doi: 10.1007/978-3-319-04501-6_9
   
   

Structural dynamics – Programming Seminar      

The focus of this seminar is on state-of-the-art numerical methods in nonlinear structural dynamics and their numerical implementation in MATLAB. The numerical tool suite (NLvib) developed for this course is published  as open source software (cf. publication list).

• Since 01/2020: Postdoctoral Researcher with aim of state doctoratem Institute of Aircraft Propulsion Systems, University of Stuttgart, Germany.
• 12/2019: Graduation as Dr.-Ing., (equivalent to PhD ), Faculty of Aerospace Engineering and Geodesy, University of Stuttgart, Germany.
  Thesis: Numerical analysis of flutter-induced multi-wave vibrations of bladed disks with tip-shroud friction
• 11/2013 – 12/2019: Research Assistant at the University of Stuttgart
  • 06/2016 – 12/2019 Institute of Aircraft Propulsion Systems (ILA)
  • 11/2013 – 05/2016 Institute of Nonlinear Mechanics (INM)
• 07/2011 – 09/2012 : Visiting Researcher, Georgia Institute of Technology, Atlanta, Georgia, USA.
  Research topic: Evaluation of near surface material degradation in concrete using nonlinear Rayleigh surface waves,
  Advisor: Prof. Laurence J. Jacobs
  
• 10/2007 – 10/2013: Studies in Mechanical Engineering, Degree program Technology Management (Dipl.-Ing.) at the University of Stuttgart, Germany.

• 2023 Best Paper Award, International Gas Turbine Institute, Structures and Dynamics, ASME, USA
• 2022 Best Paper Award, International Gas Turbine Institute, Structures and Dynamics, ASME, USA
• 2021 Baden-Württemberg Stiftung ELITE postdoctoral scholarship 
• 2020 Best Paper Award, Journal of Vibration and Acoustics, ASME, USA
• 2018 Best Tutorial Award, International Gas Turbine Institute, ASME, USA
• 07/2011 – 09/2012 DAAD Foreign exchange scholarship at Georgia Institute of Technology

We are permanently looking for suitable candidates for final theses and student assistantships. The following list is a selection of topics from the last two years.

• "Development of a nonlinear FSI method for simulation of airfoil flutter with and without impact absorbers" - Master thesis , 2023, University of Stuttgart
• "Development of a Parallel Adaptive Harmonic Refinement Method for Nonlinear Long-Periodic Vibrations based on Harmonic Balance (HB)" - Master thesis, 2023, University of Stuttgart
• "Development of a Holistic Nonlinear Frequency Domain Approach for Rotordynamics with Gas Foil Bearings" - Master thesis, 2023, University of Stuttgart
• "Development of a contact interface model order reduction method using BEM" - Bachelor thesis, 2023, University of Stuttgart
• "Development of a 'nonlinear Component Mode Synthesis' Methode" - Master thesis, 2023, University of Stuttgart
• "Possibilities and Limitations of state-of-the-art non-linear analysis methods compared to methods accepted and adapted in industry - An analyis of bearing nonlinearities" - Master thesis, 2022 , Airbus Defence and Space GmbH and University of Stuttgart
• "Modeling Variability of friction-damped structures using nonlinear modal analysis and synthesis" - Master thesis, 2022, University of Stuttgart

2018 Foundation of a company (Transfer- und Gründerunternehmung) within the TTI GmbH (technology transfer initiative). I founded the company NoVibTech based on my initiative as researcher at the University of Stuttgart. As the director of this company I am happy to have already acquired nameable companies from the German turbomachinery, automotive and machine tool industries as my customers.

Since then, the NoVibTech team has successfully completed numerous industrialization projects of numerical methods for vibration prediction developed here at the institute and by other research groups. These include industrialized software solutions:

• for the prediction of externally and self-excited vibrations, taking into account dynamic contact interactions in the frequency domain (Harmonic Balance Method) [ doi: 10.1115/1.4063769, doi: 10.1115/1.4044772],
• for the prediction of non-smooth contact interactions of elastic structures in the time domain [ doi: 10.1016/j.compstruc.2021.106698, doi: 10.1016/j.ymssp.2022.109410],
• for reduced order modeling and prediction of the vibration behavior [ doi: 10.1115/GT2017-63019], as well as identification [ doi: 10.1115/1.4055019] of mistuned bladed disks,
• and many more.

We always evaluate the reliability and performance of the developed numerical methods scientifically against the current state of the art and the measurements carried out at our institute or by our partners. 

Our Idea:
Our main focus lies in the development of software solutions for the calculation of the vibration behavior of structures which, due to their complexity cannot be calculated at all or at least not efficiently enough using conventional finite element software packages.

Our target group :
Companies that are technology leaders in their respective industries (turbo machinery, automotive, etc.). These business partners can meet their technological challenges with the latest state-of-the-art solutions. Business customers resulting from research cooperations, including publicly funded projects. In particular, university institutions and partner companies.