Bulk hydrodynamic stability and turbulent saturation in compressing hot spots

Journal Article · 20 April 2018 · Physics of Plasmas

DOI: https://doi.org/10.1063/1.5026413 · OSTI ID:1466039

Davidovits, Seth ^[1]; Fisch, Nathaniel J.  ^[2]

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1. Princeton Univ., Princeton, NJ (United States)
2. Princeton Univ., Princeton, NJ (United States); Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Here, for hot spots compressed at constant velocity, we give a hydrodynamic stability criterion that describes the expected energy behavior of non-radial hydrodynamic motion for different classes of trajectories (in ρR — T space). For a given compression velocity, this criterion depends on ρR, T, and dT/d(ρR) (the trajectory slope) and applies point-wise so that the expected behavior can be determined instantaneously along the trajectory. Among the classes of trajectories are those where the hydromotion is guaranteed to decrease and those where the hydromotion is bounded by a saturated value. We calculate this saturated value and find the compression velocities for which hydromotion may be a substantial fraction of hot-spot energy at burn time. The Lindl “attractor” trajectory is shown to experience non-radial hydrodynamic energy that grows towards this saturated state. Furthermore, comparing the saturation value with the available detailed 3D simulation results, we find that the fluctuating velocities in these simulations reach substantial fractions of the saturated value.

• Research Organization: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: PHY-1506122; NA0001836; SC0014664
• OSTI ID: 1466039
• Alternate ID(s): OSTI ID: 1434193
• Journal Information: Physics of Plasmas, Vol. 25, Issue 4; ISSN 1070-664X
• Publisher: American Institute of Physics (AIP)Copyright Statement
• Country of Publication: United States
• Language: English