TY - JOUR AU - Lelkes, János AU - Kalmár-Nagy, Tamás TI - Analysis of a piecewise linear aeroelastic system with and without tuned vibration absorber JF - NONLINEAR DYNAMICS J2 - NONLINEAR DYNAM VL - 103 PY - 2021 IS - 4 SP - 2997 EP - 3018 PG - 22 SN - 0924-090X DO - 10.1007/s11071-020-05725-0 UR - https://m2.mtmt.hu/api/publication/31379698 ID - 31379698 N1 - Cited By :3 Export Date: 5 July 2022 CODEN: NODYE Correspondence Address: Lelkes, J.; Department of Fluid Mechanics, Hungary; email: lelkes@ara.bme.hu Funding details: Science Foundation Ireland, SFI, 07/CE/1142 Funding text 1: This research was funded by Science Foundation Ireland under the Research Frontiers program. The presentation was funded by Grant 07/CE/1142, Centre for Next Generation Localisation (CNGL). AB - The dynamics of a two-degrees-of-freedom (pitch–plunge) aeroelastic system is investigated. The aerodynamic force is modeled as a piecewise linear function of the effective angle of attack. Conditions for admissible (existing) and virtual equilibria are determined. The stability and bifurcations of equilibria are analyzed. We find saddle-node, border collision and rapid bifurcations. The analysis shows that the pitch–plunge model with a simple piecewise linear approximation of the aerodynamic force can reproduce the transition from divergence to the complex aeroelastic phenomenon of stall flutter. A linear tuned vibration absorber is applied to increase stall flutter wind speed and eliminate limit cycle oscillations. The effect of the absorber parameters on the stability of equilibria is investigated using the Liénard–Chipart criterion. We find that with the vibration absorber the onset of the rapid bifurcation can be shifted to higher wind speed or the oscillations can be eliminated altogether. LA - English DB - MTMT ER - TY - JOUR AU - Kalmár-Nagy, Tamás AU - Amann, A. AU - Kim, D. AU - Rachinskii, D. TI - The Devil is in the details: Spectrum and eigenvalue distribution of the discrete Preisach memory model JF - COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION J2 - COMMUN NONLIN SCI NUMER SIMULAT VL - 77 PY - 2019 SP - 1 EP - 17 PG - 17 SN - 1007-5704 DO - 10.1016/j.cnsns.2019.04.023 UR - https://m2.mtmt.hu/api/publication/30710176 ID - 30710176 N1 - Cited By :1 Export Date: 25 September 2019 Correspondence Address: Rachinskii, D.; Department of Mathematical Sciences, The University of Texas at Dallas, 800 W. Campbell Rd., United States; email: dmitry.rachinskiy@utdallas.edu Cited By :3 Export Date: 22 September 2021 Correspondence Address: Rachinskii, D.; Department of Mathematical Sciences, 800 W. Campbell Rd., United States; email: dmitry.rachinskiy@utdallas.edu Funding details: National Science Foundation, NSF, 1413223, DMS-1413223 Funding details: National Sleep Foundation, NSF Funding details: Budapesti Műszaki és Gazdaságtudományi Egyetem, BME Funding details: Wallace H. Coulter Department of Biomedical Engineering, BME Funding details: Emberi Eroforrások Minisztériuma, EMMI Funding text 1: The authors thank M. Arnold for a stimulating discussion of the results. D. R. acknowledges the support of NSF through grant DMS-1413223. The research by T. K.-N. is supported by the Higher Education Excellence Program of the Ministry of Human Capacities in the frame of Water Science & Disaster Prevention research area of Budapest University of Technology and Economics (BME FIKP-VÍZ). Funding text 2: The authors thank M. Arnold for a stimulating discussion of the results. D. R. acknowledges the support of NSF through grant DMS-1413223 . The research by T. K.-N. is supported by the Higher Education Excellence Program of the Ministry of Human Capacities in the frame of Water Science & Disaster Prevention research area of Budapest University of Technology and Economics (BME FIKP-VÍZ). LA - English DB - MTMT ER - TY - JOUR AU - Kalmár-Nagy, Tamás AU - Wahi, P AU - Halder, A TI - Dynamics of a Hysteretic Relay Oscillator with Periodic Forcing JF - SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS J2 - SIAM J APPL DYN SYST VL - 10 PY - 2011 IS - 2 SP - 403 EP - 422 PG - 20 SN - 1536-0040 DO - 10.1137/100784606 UR - https://m2.mtmt.hu/api/publication/2835837 ID - 2835837 LA - English DB - MTMT ER - TY - JOUR AU - Kalmár-Nagy, Tamás AU - Shekhawat, Ashivni TI - Nonlinear dynamics of oscillators with bilinear hysteresis and sinusoidal excitation JF - PHYSICA D: NONLINEAR PHENOMENA J2 - PHYSICA D: NONLINEAR PEHONOM VL - 238 PY - 2009 IS - 17 SP - 1768 EP - 1786 PG - 19 SN - 0167-2789 DO - 10.1016/j.physd.2009.06.016 UR - https://m2.mtmt.hu/api/publication/2826465 ID - 2826465 N1 - Admin megjegyzés-24791014 #JournalID1# Name: Physica D: Nonlinear Phenomena ISSN: 0167-2789 #JournalID2# AB - The transient and steady-state response of an oscillator with hysteretic restoring force and sinusoidal excitation are investigated. Hysteresis is modeled by using the bilinear model of Caughey with a hybrid system formulation. A novel method for obtaining the exact transient and steady-state response of the system is discussed. Stability and bifurcations of periodic orbits are studied using Poincaré maps. Results are compared with asymptotic expansions obtained by Caughey. The bilinear hysteretic element is found to act like a ‘soft spring’. Several sub-harmonic resonances are found in the system, however, no chaotic behavior is observed. Away from the sub-harmonic resonance the asymptotic expansions and the exact steady-state response of the system are seen to match with good accuracy. LA - English DB - MTMT ER -