Computational Scientist/Engineer

Fiat Lux is seeking a computationalist with a background in plasma physics or fusion science. Fiat Lux has an opportunity to work on multispecies MHD simulations to investigate the role of non-hydrogenic species in determining the access requirements to the quiescent H-mode (QH-mode) regime. We are interested in candidates at all levels, from new Ph.D. graduates to more senior candidates for defining and leading a research program. 

For full consideration apply before November 2nd, 2023 with the potential for in-person interviews during APS-DPP 2023 annual meeting.

The work location for this position is on site at DIII-D in San Diego, California.

Applications accepted (resume or CV and cover letter) and more information can be obtained by emailing careers@fiatlux.energy.

KEY RESPONSIBILITIES

• Simulate the QH-mode regime on the DIII-D tokamak with a multi-component plasma formulation of the NIMROD MHD code

• Validate the resulting dynamics against local plasma diagnostics to produce confidence in the model

• Investigate the role of non-hydrogenic species in determining the access requirements to the QH-mode regime

• Publish and disseminate the results of this work

• Define and develop research programs

REQUIRED SKILLS

• Experience with Plasma Physics and/or Fluid Dynamics research.

• Ability to communicate science and engineering concepts to knowledgeable colleagues

• Ability to work within a small company, directly across functions within the company, and with remote collaborators

DESIRED SKILLS

• Experience with application of the MHD equations

• Familiarity with numerical methods such as finite difference, finite element, particle-in-cell methods, Monte Carlo methods and implicit time discretization

• Familiarity with plasma diagnostics such as beam-emission spectroscopy, electron cyclotron emission imaging, charge-exchange recombination and Thompson scattering

• Experience generating equilibrium reconstructions including temperature, density, and flow profiles (kinetic EFITs).

• Familiarity with one or more of distributed memory (MPI) computing; thread-based, vector-instruction based, GPU computing

EDUCATION AND EXPERIENCE

PhD in computational science and/or engineering

COMPENSATION

Fiat Lux offers a competitive compensation package. The base annual salary for this position is negotiable and dependent on candidate work location and experience. The expected base annual salary range is $90,000 to $120,000 with additional benefits for medical, dental, and vision insurance and a 401k match.

COMPANY DESCRIPTION

Fiat Lux’s mission is to accelerate the development of fusion energy by providing computational and scientific research and consulting in plasma physics. We partner on government-funded open-science research and commercial projects that build the basis of a fusion energy future.

We are committed to outstanding science, reproducibility, ethical conduct, inclusivity, and transparency. Our values guide our scientific work and publications, ensuring that our research is conducted with the highest standards of integrity and that our results are communicated both in accord with the needs of our clients and in service of the broader scientific community. We embody these values in our codes and algorithms through verification and validation, and in our software with modern unit and regression testing.

INITIAL RESEARCH DESCRIPTION

This work will enable improved understanding of the scientific basis for DIII-D Quiescent H-mode (QH-mode) by leveraging recent computational developments of the NIMROD code. Experimentally, it is established that the QH-mode tokamak operation regime is free of edge-localized modes (ELMs) with good energy confinement. ELMs produce an impulsive heat-flux on the divertor that is unacceptable under burning-plasma conditions. Beyond DIII-D in future high-power-density tokamaks, accommodation of a high heat flux at the divertor represents a key challenge to overcome. Proposed solutions involve operation at high divertor density to achieve divertor detachment, operation with a liquid lithium wall and/or introduction of impurities to enhance radiative losses. Additionally, the first wall material is likely to be a high-Z material such as Tungsten in future devices as materials such as graphite tiles restrict the lifetime of the first wall due to a high erosion rate. While the atomic species composition of the plasma is known to impact the edge-pedestal structure and stability, the specifics of the underlying physics basis for this interaction is not firm. Studying this interaction is the objective of this research without focusing specifically on the fine details of the first wall and divertor solution. The primary goal is to lay the groundwork to establish the compatibility of the divertor solutions and wall material with pedestal solutions that eliminate ELMs by leveraging present DIII-D experiments.