Modeling and theoretical analysis of a stochastic novel vibro-impact galloping energy harvester with a U-shaped base

This paper proposes a novel vibro-impact galloping energy harvester (VIGEH) with a U-shaped base. Different from classical galloping energy harvesters (GEHs), the design of the U-shaped base can avoid the damage of GEH during operation at high wind speeds by limiting the amplitude of the bluff body. The joint transition stationary probability density function (PDF) of the VIGEH is studied by further introducing the energy loss based on the stochastic averaging method. Afterward, various parameters of the VIGEH are analyzed and the results show that the smaller the distance between the rigid barriers, the higher the bump at the boundary of the joint PDF. The mean square voltage (MSV) and mean square displacement (MSD) of the VIGEH are also analyzed and the results show that the MSV and MSD are significantly enhanced when the galloping phenomenon occurs. In addition, the displacement and voltage of VIGEH and the ones of classical GEHs are compared, and the results show that the U-shaped base is effective in limiting the amplitude of the bluff body. When the input energy is the same, the output voltage of the VIGEH is higher due to the limitation of the rigid barriers which makes the bluff body vibrate at a faster frequency.