Neutronics Modeling of Inertial Confinement Fusion Targets and Chambers

What is Nuclear Fusion?

Nuclear fusion is the process that occurs in the cores of stars where two atomic nuclei combine to create a heavier nucleus and release excess energy. Harnessed as a renewable energy source, fusion could produce near limitless power. The reaction however, requires incredibly high pressure or temperature conditions that are difficult to sustain for commercial use.

Inertial Confinement Fusion

Inertial confinement fusion is one of the most promising approaches to consistent, high-energy yield fusion. This design utilizes high-energy lasers to compress a target composed of deuterium and tritium - hydrogen isotopes- under 300 Gbars of pressure. This implosion converts the solid target into a plasma, a highly energized gas. The plasma is confined by its inertia for less than a nanosecond, during which fusion ignition occurs. In ignition, the plasma outputs more energy than required to induce the reaction, and produces a hot alpha particle and an energized neutron. The energy released from the reaction manifests as heat that converts water to steam and turns a turbine to produce electricity.

Neutronics Modeling

The neutron byproducts carry 80% of the energy from the reaction which impact the stability of the reaction and the reactor. Understanding neutron behavior is critical to...

1.) Maximizing energy generation. Understanding the energy and behavior of the neutrons enables the optimization of reactor design for higher net energy gain.

2.) Producing tritium fuel. Neutrons collide with lithium "blanket" surrounding the target in a chemical reaction that breeds tritium.

3.) Understanding reactor degradation and irradiation. The neutron flux damages reactor walls that can lead to material swelling and reactor embrittlement.

As such, neutron simulation, also known as neutronics, is a valuable asset in optimizing reactor design. In my research, I will be designing and constructing an analytical neutronics model that will predict the effects of reactor design and fusion reaction parameters on neutron behavior. We will begin by simulating atomic-scale fusion reactions and extrapolate those results to larger scales, modeling chamber physics and eventually reactor level diagnostics.

Page updated

Report abuse