Power Reclamation Efficiency of a Miniature Energy Harvesting Device Using Internal Fluid Flows

This study comprises experimental energy harvesting results of a miniature internal liquid flow power reclamation device. The system’s reclamation principal is basically related to translation of mechanical energy and its conversion into electrical energy. The translation phase is concerned about capturing vibrations caused in the device by inner liquid flow via device tails, which are designed by taking inspiration from black ghost knife fish (Apteronotus albifrons) body shape. On the other hand, the conversation phase is attained by the rotating movement of the mentioned tails so that the rotating circular waterproof magnet structure could yield power through magnetic polarization. A simple current amplifier increases the voltage obtained, and the reclaimed power is transferred to the 3.76V (Ni-Mg) batteries. The efficiency tests were performed within a range of flow velocities (1.0 m/s ∼ 5.0 m/s) under various fluid densities (fresh water, low dense and high dense water) and different ambient temperatures (22 and 38 °C) in order to obtain a comparative parametric data about the device response to internal fluid flow. In optimum test conditions (fresh water as working fluid and 38°C ambient temperature) the device harvested up to 17, 26 Watts of energy.