Additive Manufactured RF Metamaterials for Plasma Simulation
Additive Manufactured RF ...

Additive Manufactured RF Metamaterials for Plasma Simulation

In your project you will use FEM simulations in COMSOL to simulate the interaction of a 4.6GHz lower hybrid wave with a cold plasma dielectric and simulate the wave propagation. Using these results you will use COMSOL to design an RF metamaterial that emulates the cold plasma dielectric relation, and produce the metamaterial with additive manufacturing. This metamaterial will be designed to be additive manufactures using FDM or resin-based 3D printing to simplify construction. Conductive channels will be printed into a block of plastic and filled with wire or low-melting-temperature alloy. By using this metamaterial as a load on a lower hybrid antenna designed for the DIII-D tokamak, you will compare antenna performance and probed RF wave path to predictions in FEA simulation.

Posting date: November 26, 2024

A middle-aged white man with thick glasses, a blue polo, and dark, short hair smiles mildly
Andrew Seltzman
Research Scientist
01
Description

How do you test an antenna system designed to launch an RF wave into a fusion reactor on the test bench before you install the antenna in the reactor? The interaction between the antenna and the plasma it is launching an RF wave into, and the path a radio wave propagates through space, is determined by the dielectric constant, or permittivity, of the space. An ordinary dielectric, such as Teflon, is considered isotropic (the wave interaction does not depend on the direction the wave propagates or the orientation of the electric field), uniform (the dielectric does not vary along the path of propagation of the wave), and non-dispersive (wave velocity does not depend of frequency). The free electrons and magnetic field in a plasma has properties makes a plasma dielectric anisotropic, non-uniform, and dispersive; properties that control how the antenna structure couples power into the plasma, and how it propagates. These properties are difficult to replicate in non-plasma dielectrics, but can be emulated with metamaterials. An RF metamaterial is engineered to have properties that are not typically found in nature by the addition of conductive structures within the dielectric, such as grills, bars, or c shaped resonators. The construction of a metamaterial with numerous precisely placed elements is time consuming, making these structures difficult to fabricate.
In your project you will use FEM simulations in COMSOL to simulate the interaction of a 4.6GHz lower hybrid wave with a cold plasma dielectric and simulate the wave propagation. Using these results you will use COMSOL to design an RF metamaterial that emulates the cold plasma dielectric relation, and produce the metamaterial with additive manufacturing. This metamaterial will be designed to be additive manufactures using FDM or resin-based 3D printing to simplify construction. Conductive channels will be printed into a block of plastic and filled with wire or low-melting-temperature alloy. By using this metamaterial as a load on a lower hybrid antenna designed for the DIII-D tokamak, you will compare antenna performance and probed RF wave path to predictions in FEA simulation.

02
Reference

https://www.nature.com/articles/s41598-018-24250-0.pdf

Apply for this position

Head to MIT's UROP site to apply for this opportunity.

Explore Professor’s profile