Sample interview questions: Can you discuss your knowledge of plasma equilibrium reconstruction algorithms for reversed-field pinches?
Sample answer:
Equilibirum Reconstruction Techniques for Reversed-Field Pinches (RFPs)
RFPs are unique toroidal fusion devices with a complex plasma behavior and strong magnetic shear. Equilibrium reconstruction algorithms play a crucial role in understanding and controlling RFP plasmas.
Reconstruction Approaches:
- Analytical Models: Simplified analytical models based on force balance equations and assumed plasma profiles.
- Numerical Codes: Use numerical techniques (e.g., finite element analysis, magnetohydrodynamic simulations) to solve for the equilibrium solution.
- Data-Driven Methods: Utilize experimental measurements (e.g., magnetic diagnostics, spectroscopy) to estimate the equilibrium parameters.
Specific Algorithms for RFPs:
- FLUX-C: 1D code that solves the Grad-Shafranov equation for cylindrical geometry, taking into account the specific boundary conditions of an RFP.
- 3DR-FIT: 3D code that reconstructs the equilibrium using experimental magnetic field data and a set of basis functions.
- RTQLIB: Reconstruction library that includes various algorithms, including those tailored for RFPs, such as the non-linear force-fit method and the EFIT-like equilibrium solver.
- JFIT: 1D code that estimates the current profile from magnetic field and … Read full answer