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Updated: Sep 14, 2025
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A Polymer-based Piezoelectric Vibration Energy Harvester with a 3D Meshed-Core Structure
Published on: February 20, 2019
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Vibration energy harvesting by ferrofluids in external magnetic fields
Michal Rajnak1,2, Juraj Kurimsky3, Katarina Paulovicova4
1Institute of Experimental Physics SAS, Watsonova 47, 04001, Košice, Slovakia. rajnak@saske.sk.
Scientific Reports
|July 22, 2025
Summary
This study presents a ferrofluid sloshing energy harvester for powering distributed sensors. Optimal performance is achieved with a magnetic field perpendicular to motion and gravity, showing linear power increase with ferrofluid magnetization.
Area of Science:
- Materials Science
- Electrical Engineering
- Physics
Background:
- Wearable electronics and big data necessitate sustainable power for distributed sensors.
- Ferrofluids offer unique properties for energy harvesting applications.
Purpose of the Study:
- To design and experimentally investigate a ferrofluid sloshing energy harvester.
- To analyze the impact of magnetic field configuration and ferrofluid properties on energy harvesting efficiency.
Main Methods:
- A cylindrical vial half-filled with ferrofluid was subjected to controlled shaking.
- Induced voltage in a nearby coil was measured under varying shaking rates and magnetic field configurations.
- Five ferrofluid samples with different magnetizations were tested.
Main Results:
- The most effective energy harvesting occurred when the magnetic field was perpendicular to both vial motion and gravity.
- Harvested electric power increased linearly with the ferrofluid's magnetization of saturation.
- A reduction in induced voltage was observed in stronger magnetic fields due to the magneto-viscous effect.
Conclusions:
- Ferrofluid sloshing is a viable method for mechanical energy harvesting.
- The findings provide insights for optimizing ferrofluid energy harvesters for applications with dynamic mechanical excitations and magnetic fields.
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