Direct gyrokinetic comparison of pedestal transport in JET with carbon and ITER-like walls

@article{Hatch2019DirectGC,
  title={Direct gyrokinetic comparison of pedestal transport in JET with carbon and ITER-like walls},
  author={Don Hatch and M. Kotschenreuther and Swadesh M. Mahajan and Gabriele Merlo and A. R. Field and Carine Giroud and Jon C. Hillesheim and Costanza F Maggi and Christian Perez von Thun and Colin M. Roach and S. Saarelma},
  journal={Nuclear Fusion},
  year={2019},
  volume={59}
}
This paper compares the gyrokinetic instabilities and transport in two representative JET pedestals, one (pulse 78697) from the JET configuration with a carbon wall (C) and another (pulse 92432) from after the installation of JET’s ITER-like Wall (ILW). The discharges were selected for a comparison of JET-ILW and JET-C discharges with good confinement at high current (3 MA, corresponding also to low ) and retain the distinguishing features of JET-C and JET-ILW, notably, decreased pedestal top… 

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References

SHOWING 1-10 OF 84 REFERENCES

A gyrokinetic perspective on the JET-ILW pedestal

JET has been unable to recover historical confinement levels when operating with an ITER-like wall (ILW) due largely to the inaccessibility of high pedestal temperatures. Finding a path to overcome

Global and pedestal confinement in JET with a Be/W metallic wall

Type I ELMy H-mode operation in JET with the ITER-like Be/W wall (JET-ILW) generally occurs at lower pedestal pressures compared to those with the full carbon wall (JET-C). The pedestal density is

Dimensionless scalings of confinement, heat transport and pedestal stability in JET-ILW and comparison with JET-C

Three dimensionless scans in the normalized Larmor radius ρ*, normalized collisionality ν* and normalized plasma pressure β have been performed in JET with the ITER-like wall (JET-ILW). The

Pedestal evolution physics in low triangularity JET tokamak discharges with ITER-like wall

The pressure gradient of the high confinement pedestal region at the edge of tokamak plasmas rapidly collapses during plasma eruptions called edge localised modes (ELMs), and then re-builds over a

Comparative analysis of core heat transport of JET high density H-mode plasmas in carbon wall and ITER-like wall

A consistent deterioration of global confinement in H-mode experiments has been observed in JET [] following the replacement of all carbon plasma facing components (PFCs) with an all metal

The effect of a metal wall on confinement in JET and ASDEX Upgrade

In both JET and ASDEX Upgrade (AUG) the plasma energy confinement has been affected by the presence of a metal wall by the requirement of increased gas fuelling to avoid tungsten pollution of the

Gyrokinetic projection of the divertor heat-flux width from present tokamaks to ITER

The XGC1 edge gyrokinetic code is used to study the width of the heat-flux to divertor plates in attached plasma condition. The flux-driven simulation is performed until an approximate power balance

MHD and gyro-kinetic stability of JET pedestals

The pedestal profile measurements in high triangularity JET plasmas show that with low fuelling the pedestal width decreases during the ELM cycle and with high fuelling it stays constant. In the low

Studies of the pedestal structure and inter-ELM pedestal evolution in JET with the ITER-like wall

The pedestal structure of type I ELMy H-modes has been analysed for JET with the ITER-like Wall (JET-ILW). The electron pressure pedestal width is independent of ρ * and increases proportionally to 

Progress at JET in integrating ITER-relevant core and edge plasmas within the constraints of an ITER-like wall

This paper reports the progress made at JET-ILW on integrating the requirements of the reference ITER baseline scenario with normalized confinement factor of 1, at a normalized pressure of 1.8
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