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Solutions and stochastic bifurcations in a vibration energy harvesting system

Title:
Solutions and stochastic bifurcations in a vibration energy harvesting system 

Speaker:
Prof Grzegorz Litak

Lublin University of Technology, Poland 

Abstract:

Vibration energy harvesting the base kinematic excitation is proposed using piezoelectric transducer and nonlinear resonator with double well potential [1]. Broadband frequency energy harvesting systems are based on nonlinear resonators. We study a bistable energy harvester consisted of the resonator with some nonlinearities induced by magnets  Ambient kinetic energy is transformed to electric energy by a piezoelectric patch installed on the elastic beam To maximize the energy harvested in systems with multiple solutions the higher amplitude response should be preferred. The investigated system is excited with the harmonic motion and the combined effect of the frame harmonic and stochastic motions [2]. Starting from initial conditions with minimum energy we observe considerable improvement of performance of the system in the presence of stochastic excitation component. Our initial calculations clearly indicate the existence of stochastic bifurcations in that system and the appearance of the subharmonic solutions [3,4]. The calculations were performed for the double well polynomial potential and the combination of the parabola corresponding to the elastic cantilever beam and  gaussian shape describing the magnetic  interaction.  The   statistics  based  on  initial  conditions   indicate  the  probability   of   distribution for  selected solutions. The appearance chaotic solution for the deterministic system was confirmed by the 0-1 test [5]


REFERENCES

  1. Litak, G., Friswell, M.I., Adhikari S. Magnetopiezoelastic energy harvesting driven by random excitations. Applied Physics Letters 96, 214103 (2010).
  2. Friswell, M.I., Bilgen, O., Ali, S.F., Litak, G., Adhikari, S. The effect of noise on the response of a vertical cantilever beam energy harvester. Z. Angew. Math. Mech. 95, 433-443 (2015).
  3. Litak, G., Ambrożkiewicz, B., Wolszczak, P. Dynamics of a nonlinear energy harvester with subharmonic responses. Journal of Physics: Conference Series 1736, 012032 (2021).
  4. Cunha Jr, A., Litak, G., Wolszczak, P. Effect of stochastic excitation on sub-harmonic solutions in a bistable energy harvester. AIP Conference Proceedings 2425, 410003 (2022).
  5. Bernardini, D., G Litak, G. An overview of 0–1 test for chaos, Journal of the Brazilian Society of Mechanical Sciences and Engineering 38, 1433-1450 (2016).

Biography:

Prof. Grzegorz Litak completed his M.Sc. degree in physics at Skłodowska (UMCS) in Lublin, in 1988. Later, working on the effect of disorder on correlated and exotic superconductors, he received his Ph.D (1994) and D.Sc (2002) degrees from the same University. After defending his Ph.D thesis he moved to in Lublin where he is presently working as a full professor. From 1994 he also started his research on nonlinear dynamics. He focused on bifurcation theory, chaotic dynamics and nonlinear time series analysis. Recently, he was also involved in research on mechanical and thermal energy harvesting, focusing on frequency broadband effects. G. Litak published about 400 papers including about 330 in the international journals.

Employment and positions

  •  1994-2016Lublin University of Technology, Department of Applied Mechanics and Institute of Information Technology, Assistant Professor (till 2004) - Associate  Professor (till 2014) - Full Professor (till 2016)

  • 2015-2017    Institut National des Sciences Appliquées de Lyon, France, Laboratoire deGénie Electrique et Ferroélectricité, Visiting Professor

  • 2016-2018        AGH University of Science and Technology in Kraków, Poland, Departmentof Process Control, Professor (1/4 position)

  • 2016-now          Lublin University of Technology, Department of Automation, Head of Department, Full Professor