Visco–resistive dissipation in transient reconnection driven by the Orszag–Tang vortex
Armstrong, C. K., & Craig, I. J. D. (2013). Visco–Resistive Dissipation in Transient Reconnection Driven by the Orszag–Tang Vortex. Solar Physics, 283(2), 1-9.
Permanent Research Commons link: https://hdl.handle.net/10289/7254
Viscous effects are expected to significantly contribute to reconnective energy release mechanisms in solar flares. While simple scaling arguments based on head-on reconnection suggest that viscous dissipation may dominate resistive dissipation, it is not clear whether these findings can be applied in more general merging situations. Here we perform side-by-side planar reconnection simulations driven by the Orszag-Tang vortex, for both classical and Braginskii forms of the viscosity. This formulation has the advantage of providing an autonomous MHD system that develops strong current layers, sustained by large-scale vortical shearing flows. The dissipation rates are shown to follow analytically based scaling laws, which suggest that viscous losses generated from large-scale non-uniform velocity fields are likely to dominate resistive losses in current-sheet reconnection solutions.