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Abstract This study proposes an application of lightweight vibration control strategy known as nonlinear energy sink (NES) to mitigate the undesired vibrations in engine crankshaft systems. Linear vibration absorbers have long been used to suppress undesired vibrations. These devices can be tuned to reduce vibrations at a single frequency while adding extra inertia to the powertrain system. On the contrary, the NES is a lightweight vibration energy absorber. The presence of essential nonlinearity in the NES design provides the means for realization of irreversible targeted energy transfer (TET) from the primary system to the NES and attenuation of energy over a wide range of frequencies. This study introduces the conditions critical to achieve TET through its mathematical analysis and understanding the dynamical mechanisms governing this phenomenon in a strongly nonlinear transient dynamical system. Highlights • Nonlinear control of torsional vibrations in an engine crankshaft is studied. • An optimal design of nonlinear energy sink is developed to mitigate the vibrations. • Significant vibration absorption and improvement in system performance are achieved. • The mechanisms needed for nonlinear energy pumping from engine to NES are obtained. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an optimal design for a system comprising a nonlinear energy sink (NES) and a piezoelectric-based vibration energy harvester attached to a free–free beam under shock excitation. The energy harvester is used for scavenging vibration energy dissipated by the NES. Grounded and ungrounded configurations are examined and the systems parameters are optimized globally to both maximize the dissipated energy by the NES and increase the harvested energy by piezoelectric element. A satisfactory amount of energy has been harvested as electric power in both configurations. The realization of nonlinear vibration control through one-way irreversible nonlinear energy pumping and optimizing the system parameters result in acquiring up to 78 percent dissipation of the grounded system energy. [Copyright &y& Elsevier]