Research Needs for Magnetic Fusion Energy Sciences - US Burning ...

• Recruit, train and support dedicated analysts, who would bridge the gap between
theorists, code developers and experimentalists, providing unbiased assessments.
• Provide substantial computer time for code verification and model validation.
Scientific and technical Research
The Thrust represents a focused and systematic effort to develop robust, validated predictive modeling
capabilities for toroidal magnetically confined plasmas by integrating and amplifying many
existing and proposed elements of the fusion program, including the FsP. The physical phenomena
requiring study are broad, covering wave propagation and damping, wave particle interactions,
turbulence and transport, hydrodynamic stability, plasma-wall interactions, radiation transport
and atomic physics. The physical problem is intrinsically nonlinear, involving ensembles of particles
and fields in a six-dimensional phase space and spanning more than a factor of 10 12 in time
and 10 6 in space. a range of magnetic configurations must be addressed, including those with
both external and self-generated three-dimensional fields.
meeting this challenge will require significant advancements in theory and computation, along
with a coordinated experimental program involving innovative diagnostics and systematic validation
studies. success would require additional resources supporting all of the actions listed earlier
and more significantly, an unprecedented degree of cooperation among major program elements.
activities would be iterative and ongoing with a cycle of model development, testing and
analysis at their core.
Elements of Thrust
Work on the Thrust would begin by selecting a set of “case studies” for initial attack. The case
studies would represent important areas of focus that allow for rational prioritization and maximum
impact on the overall fusion sciences program. criteria for selection would include importance,
urgency and readiness. one such set was discussed by the predictive modeling panel (described
in chapter 2) and is supplemented here by ideas from Themes 1, 3, and 5. These case studies,
with references to technical detail in other theme chapters and sections, are provided in table
1. They are provided only as examples; considerable discussion would be required to arrive at a final
list. available resources would dictate the feasible scale of effort in the short term — though
ultimately all topics will need to be addressed.
For each case study chosen, careful planning will be carried out to map research needs and directions.
Planning would begin with a discussion of how model predictions would be used, what applications
are intended and what the impact of predictions would be, especially the consequences
of prediction errors. Researchers would need to describe areas where the underlying physical
models are well understood and where they are uncertain or controversial, to assess which parts
of the problem are theoretically and computationally tractable and which require significant development.
important areas of physics integration and interface should also be identified. The
current state of comparison between codes and experiments should be evaluated, and important
areas of agreement and disagreement tabulated. investigators should estimate the domain over
which the model can be tested, along with the experimental platforms required. This evaluation
should map out the possible domain of validation with respect to the intended applications —
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