Implementation of Magnetostrictive Material Terfenol-D in CNG Fuel Injection Actuation

In applications broadly defined for actuation, magnetostrictive materials possess intrinsic rapid response times while providing small and accurate displacements and high-energy efficiency, which are some of the essential parameters for fast control of fuel injector valves for decreased engine emissions and lower fuel consumption. This paper investigates the application of Terfenol-D as a magnetostrictive actuator material for CNG fuel injection actuation. A prototype fuel injector assembly, including Terfenol-D as the core actuator material, was modeled in both Finite Element Method Magnetics (FEMM) and ANSYS Electromagnetics simulation softwares for 2D magnetics simulation. Preferably, FEMM was used in order to determine the coil-circuit parameters and the required flux density or applied magnetic field to achieve the desired magnetostrictive strain, consequently, the injector needle lift. The FEMM magnetic simulation was carried out with four different types of AWG coil wires and four different coil thicknesses of the entire injector assembly in order to evaluate the relationship between the different coil types and thicknesses against the achieved strain or injector lift. Eventually, the optimized parameters derived from FEMM were inserted into ANSYS Electromagnetics to compare the variation of results between these two simulation environments.