In aerospace engineering, a magnetostrictive system is used to convert mechanical vibrations or strain into electrical power. Magnetostriction is the property of certain materials that causes them to change their shape or dimensions when subjected to a magnetic field. This property can be harnessed to convert mechanical energy into electrical energy through the following process:
Magnetostrictive Material: The system utilizes a magnetostrictive material, which is typically a ferromagnetic material like Terfenol-D. Terfenol-D is an alloy of terbium, dysprosium, and iron, and it exhibits significant magnetostrictive properties.
Mechanical Vibrations: In the aerospace context, vibrations or mechanical strain are generated due to various factors, such as engine vibrations, structural loads, or aerodynamic forces acting on the aircraft.
Applying Magnetic Field: The magnetostrictive material is subjected to a magnetic field. This field can be generated by using permanent magnets or electromagnets placed near or within the material.
Induced Strain: As the material experiences the mechanical vibrations, it undergoes tiny changes in shape or dimensions due to the magnetostrictive effect. The mechanical vibrations cause the material to expand and contract periodically.
Induced Electrical Signals: The strain-induced changes in the magnetostrictive material's dimensions result in a corresponding change in the magnetic field around it. This variation in the magnetic field induces electrical signals in nearby conductive coils or wires.
Electrical Power Generation: The induced electrical signals can be harnessed by the surrounding coils or wire windings to produce electrical power. This power can then be used to charge batteries, power sensors, avionics, or any other electrical systems in the aerospace vehicle.
Magnetostrictive energy harvesters have the advantage of being lightweight, reliable, and capable of capturing a wide range of frequencies. They can be integrated into various aerospace structures to scavenge energy from the environment and contribute to the overall power needs of the aircraft. However, the efficiency of the energy conversion process depends on various factors, including the material properties, the intensity of the mechanical vibrations, and the design of the energy harvesting system. Engineers continuously work on optimizing and improving these systems to enhance their energy capture capabilities in aerospace applications.