Mendoza M, Muñoz J D
Simulation of Physical Systems Group, Universidad Nacional de Colombia, Departamento de Fisica, Bogotá DC, Colombia.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Feb;77(2 Pt 2):026713. doi: 10.1103/PhysRevE.77.026713. Epub 2008 Feb 29.
We develop a three-dimensional (3D) lattice Boltzmann model that recovers in the continuous limit the two-fluids theory for plasmas, and consequently includes the generalized Ohm's law. The model reproduces the magnetic reconnection process just by giving the right initial equilibrium conditions in the magnetotail, without any assumption on the resistivity in the diffusive region. In this model, the plasma is handled similar to two fluids with an interaction term, each one with distribution functions associated to a cubic lattice with 19 velocities (D3Q19). The electromagnetic fields are considered as a third fluid with an external force on a cubic lattice with 13 velocities (D3Q13). The model can simulate either viscous fluids in the incompressible limit or nonviscous compressible fluids, and successfully reproduces both the Hartmann flow and the magnetic reconnection in the magnetotail. The reconnection rate in the magnetotail obtained with this model lies between R=0.062 and R=0.073, in good agreement with the observations.
我们开发了一种三维（3D）格子玻尔兹曼模型，该模型在连续极限下恢复了等离子体的双流体理论，因此包含广义欧姆定律。该模型仅通过在磁尾给出正确的初始平衡条件就能再现磁重联过程，而无需对扩散区域的电阻率做任何假设。在这个模型中，等离子体被当作具有相互作用项的两种流体来处理，每种流体都有与具有19个速度的立方晶格相关联的分布函数（D3Q19）。电磁场被视为在具有13个速度的立方晶格（D3Q13）上受外力作用的第三种流体。该模型既可以模拟不可压缩极限下的粘性流体，也可以模拟无粘性可压缩流体，并且成功再现了哈特曼流和磁尾中的磁重联。用该模型得到的磁尾重联率在R = 0.062到R = 0.073之间，与观测结果吻合良好。
