Theory and simulations of micro-tearing mode using BOUT++ code

Micro-tearing mode (MTM) has been suggested as one of the potential driving mechanisms crucial for pedestal plasma turbulence transport [1]. Recently, the classical Hazeltine electric conductivity model [2] has been extended to include radial variation by Larakers et.al. [3]. We revisited this derivation, derived dispersion relations in various limiting cases, and compared them with different MTM models in the literature. We found that the general electric conductivity reduces to Drake model [4] in both the collisional limit and the semi-collisional limit limits with a Lorentz gas collision operator. We also found that if the electron inertia term is retained in Hassam’s fluid MTM model [5], the result is consistent with Drake and Larakers models in the collisional limit. Based on extended Hassam model, the BOUT++ six-field-two fluid model has been extended to include the MTM. The preliminary fluid simulation results with MTM will be presented.



[1] D. Hatch et.al., Nucl. Fusion 56, 104003 (2016)

[2] R. Hazeltine et.al., Phys. Fluids 18, 1778 (1975)

[3] J. Larakers et.al., Phys. Plasmas 27, 062503 (2020)

[4] J. Drake and Y. Lee, Phys. Fluids 20, 1341 (1977)

[5] A. Hassam, Phys. Fluids 23, 2493 (1980)