Three-Dimensional Numerical Simulations of Interaction Between Flux Ropes in the Solar Corona

We have recently identified in three-dimensional (3D) reduced magnetohydrodynamics (RMHD) simulations that interaction between magnetic flux ropes is a fundamental process in the solar corona that leads to current-sheet formation, 3D magnetic reconnection, and coronal heating. In the case of long flux ropes, this process essentially reduces to the coalescence of magnetic islands in 2D, which we have also studied extensively using MHD simulations. In the high-Lundquist number (S) limit, which requires high-resolution to simulate, the reconnection rate between the flux ropes becomes small following the Sweet-Parker description, and thus they bounce back and forth while they reconnect. We will present 3D simulations to demonstrate this process, which can potentially have great implications in the generation of Alfven waves and MHD turbulence. This work is supported by a NASA grant NNX08BA71G, and a NSF grant AGS-0962477.