Reduced electrostatic turbulence in the quasi-isodynamic stellarator configuration CIEMAT-QI4

Abstract

CIEMAT-QI4 is a quasi-isodynamic stellarator configuration that simultaneously features very good fast-ion confinement in a broad range of β values, low neoclassical transport and bootstrap current, and ideal magnetohydrodynamic stability up to $\beta = 5\%$ . In this paper it is shown that CIEMAT-QI4 also exhibits reduced turbulent transport. This is demonstrated through nonlinear electrostatic simulations with the gyrokinetic code stella , including kinetic ions and electrons. The relation between reduced turbulent transport and the fact that CIEMAT-QI4 very approximately satisfies the so-called maximum- J property is discussed.

Keywords

• stellarators
• gyrokinetics
• turbulent transport
• optimization
• quasi-isodynamic