Physical Sciences Graduate Research Assistant Student

About the Role

The Integrated Design and Assessment (XTD-IDA) group in the X Theoretical Design (XTD) division is seeking motivated candidates for a six-month Graduate Research Assistant (GRA) position simulating small scale mixing in Double Cylinder experiments. The Double Cylinder experiments are a series of experiments fired at the Sandia Z machine that aim to understand the hydrodynamic development of features in imploding geometries, such as joints in Inertial Confinement Fusion (ICF) capsules.

In these experiments, Z is used to implode a pair of concentric cylindrical shells around a central witness rod, with 2D defects placed on the inner shell. These features are unstable and produce spikes that can interact and imprint onto the central rod. The experiments are nominally two dimensional, but simulations of the double shell experiments have found them to be sensitive to 3D effects. The focus of this position is to research the effects of small-scale mixing and how it should be modeled in these experiments.

This will involve performing 3D Implicit Large Eddy Simulations (ILES) of the experiments using the laboratory's Eulerian xRage code to gauge the computational requirements to properly simulate the mixing. Simulations in the Lagrangian FLAG code are also of interest if time permits. Additionally, 2D and 3D simulations using turbulence models are needed to understand the extent to which these mix effects can be captured in lower cost simulations, and how large-scale thermal instabilities in the exterior of the experiment that drive the mixing should be represented in the mix models.

An internal report and/or presentation is required at the end of the six months to document the performed work, and interaction with the broader research community via conferences and journal publications is encouraged.

Requirements

• Pass a new employment drug test: The Laboratory requires successful applicants to complete a new employment drug test and maintains a substance abuse policy that includes random drug testing.
• Demonstrated ability to communicate (verbal and written) well in a professional scientific context; and commitment to achieving results in a complex social and organizational setting.
• Experience working effectively as part of a team with a willingness to assist and support other team members as needed; and also have the ability to work independently.
• Proficient in the use of standard office software, such as Microsoft Office Suite applications including Word, Excel, PowerPoint, and Outlook.

Qualifications

• Have and maintain a minimum cumulative GPA of 3.2 on a 4.0 scale.
• Provide documentation of acceptance into a graduate program.
• Enroll in and successfully complete a minimum of 6 graduate credit hours per semester (or the equivalent of full time enrollment).
• All students MUST remain enrolled at their university while working at the Lab during the academic year. Students must provide the program coordinator with current, official transcripts annually to remain eligible.

Desired Skills

• Exposure to and interest in a relevant discipline such as fluid dynamics, turbulence modeling, or applied mathematics.
• Proficiency in one or more scientific programming languages (e.g., C++, Fortran, or Python).
• Undergraduate degree in physical science or engineering is preferred.

Work Location

The work location for this position is onsite and located in Los Alamos, NM. All work locations are at the discretion of management.

Benefits

• PPO or High Deductible medical insurance with the same large nationwide network.
• Dental and vision insurance.
• Free basic life and disability insurance.
• Paid childbirth and parental leave.
• Award-winning 401(k) (6% matching plus 3.5% annually).
• Learning opportunities and tuition assistance.
• Flexible schedules and time off (PTO and holidays).
• Onsite gyms and wellness programs.
• Extensive relocation packages (outside a 50-mile radius).

Due to federal restrictions, citizens of the People's Republic of China (including Hong Kong and Macau), the Islamic Republic of Iran, the Democratic People's Republic of Korea (North Korea), and the Russian Federation who are not Lawful Permanent Residents ("green card" holders) are prohibited from accessing facilities that support the mission, functions, and operations of national security laboratories and nuclear weapons production facilities, which includes Los Alamos National Laboratory.

This position does not require a security clearance. Selected candidates will be subject to drug testing and other pre-employment background checks. A Q clearance is required for this position, and obtaining such clearance requires US Citizenship except in extremely rare circumstances. Dependent upon the position, additional authorization to access classified information may be required, which may or may not be available to dual citizens.