Plasma accounts for a large proportion of matter in the universe. And all plasma, whether it is laboratory plasma, solar plasma or distant cosmic plasma, are all with magnetic field exists. Magnetic reconnection (MR) is one of the most important physical process for many dynamical phenomena in the universe. It also provides a reasonable method to release the energy stored in the magnetic field, such as solar flares and magnetosphere storms. Magnetohydrodynamical (MHD) numerical simulation is an effective way to study the potential mechanisms related to the MR. It can help us simulate the magnetic reconnection process in different environments through different parameters, initial conditions and boundary conditions, and obtain the quantitative analysis of the process of magnetic reconnection such as magnetic field, density, fluid velocity. We investigate the influence of Magnetic Reynolds number and numerical resolution on the reconnection rate, numerical diffusion and energy spectrum. We have found that magnetic Reynolds number has some impact on the reconnection rate and energy spectrum distribution. The characteristic time for engaging into the non-linear phase will be earlier as the Reynold number increases. When it comes to the tearing phase, reconnection rate will increase rapidly. On the other hand, magnetic Reynolds number Rm affects significantly the Kolmogorov microscopic scale lko , which becomes smaller as Rm increases. Additional dissipation is defined as combined effect between numerical diffusion and turbulent dissipation. We found that the additional dissipation is dominated by numerical diffusion before the tearing mode instability takes place. After the instability develops, the additional dissipation rises vastly, which indicates that turbulence can enhance the diffusion. Through the spectrum study, the energy dissipation might take place at the macroscopic MHD scale.
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