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Justin Richard Ball

Related publications (18)

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Effect of collisions on non-adiabatic electron dynamics in ITG-driven microturbulence

Stephan Brunner, Justin Richard Ball

Non-adiabatic electron response leads to significant changes in ion temperature gradient (ITG) eigenmodes, leading, in particular, to fine-structures that are significantly extended along the magnetic field lines at corresponding mode rational surfaces (MR ...

AIP Publishing2021

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Self-interaction is the process by which a microinstability eigenmode that is extended along the direction parallel to the magnetic field interacts non-linearly with itself. This effect is particularly significant in gyrokinetic simulations accounting for ...

2020

In this work, we highlight an issue that may reduce the accuracy of many local nonlinear gyrokinetic simulations – turbulent self-interaction through the parallel boundary condition. Given a sufficiently long parallel correlation length, individual turbule ...

2020

Local linear gyrokinetic simulations show that electron temperature gradient (ETG) instabilities are the fastest growing modes for ky rho i greater than or similar to 0.1

IOP PUBLISHING LTD2020

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Local gyrokinetic simulations solve the gyrokinetic equations with homogeneous background gradients, typically using a doubly periodic domain in the (x, y) plane (i.e. perpendicular to the field line). Spatial Fourier representations are almost universal i ...

2019

Specific energy (i.e. energy per unit mass) is one of the most fundamental and consequential properties of a fuel source. In this work, a systematic study of measured fusion cross-sections is performed to determine which reactions are potentially feasible ...

2019

Optimized up-down asymmetry to drive fast intrinsic rotation in tokamaks

Justin Richard Ball

Breaking the up-down symmetry of the tokamak poloidal cross-section can significantly increase the spontaneous rotation due to turbulent momentum transport. In this work, we optimize the shape of flux surfaces with both tilted elongation and tilted triangu ...

2018

Intrinsic momentum transport in up–down asymmetric tokamaks

Justin Richard Ball

Recent work has demonstrated that breaking the up–down symmetry of tokamak flux surfaces removes a constraint that limits intrinsic momentum transport, and hence toroidal rotation, to be small. We show, through MHD analysis, that ellipticity is most effect ...

Institute of Physics2014