We study the ion gyroviscous effect and Hall magnetohydrodynamic (MHD) effect separately using the modified MHD simulation of the magnetopause. Simulations show that the ion gyroviscous effect is on the order of a cha...We study the ion gyroviscous effect and Hall magnetohydrodynamic (MHD) effect separately using the modified MHD simulation of the magnetopause. Simulations show that the ion gyroviscous effect is on the order of a characteristic scale of ion Larmor radius and is mainly limited near the magnetosheath boundary. The Hall MHD effect is on the order of a characteristic scale of ion inertial length and occurs mainly in the central region of the current layer. The magnetic field component out of the simulation plane has a bipolar structure near the magnetosheath boundary from the ion gyroviscous effect and a quadrupole structure in the central region of the current layer from the Hall MHD effect. These results are of fundamental importance in understanding the reconnection processes in space and astrophysical plasma.展开更多
This paper presents the modified magnetohydrodynamic(MHD)model and simulations of solar wind-magnetosphere interactions.We use the two-dimensional and three-component,compressible,resistive,ion gyroviscous and Hall MH...This paper presents the modified magnetohydrodynamic(MHD)model and simulations of solar wind-magnetosphere interactions.We use the two-dimensional and three-component,compressible,resistive,ion gyroviscous and Hall MHD model,i.e.,including the ion Unite Larmor radius(FLR)and Hall MHD effects,but neglecting the electron inertia and electron FLR effects.The composed dynamic pressure pulses(shear variations in the How velocity)in the solar wind form gusts that continually buffet the magnetosphere and cause the time-dependent magnetic reconnection at the magnetopause.The results show that the magnetic Held and the How velocity components perpendicular to the reconnection plane can be generated in magnetopause current layer.The vortical How structures can also occur in the magnetospheric side region.These results are responsible for non-ideal MHD properties of the plasma fluid,i.e.,ion FLR and Hall MHD effects.展开更多
基金the National Natural Science Foundation of China under Grant No.49774247.
文摘We study the ion gyroviscous effect and Hall magnetohydrodynamic (MHD) effect separately using the modified MHD simulation of the magnetopause. Simulations show that the ion gyroviscous effect is on the order of a characteristic scale of ion Larmor radius and is mainly limited near the magnetosheath boundary. The Hall MHD effect is on the order of a characteristic scale of ion inertial length and occurs mainly in the central region of the current layer. The magnetic field component out of the simulation plane has a bipolar structure near the magnetosheath boundary from the ion gyroviscous effect and a quadrupole structure in the central region of the current layer from the Hall MHD effect. These results are of fundamental importance in understanding the reconnection processes in space and astrophysical plasma.
基金Supported by the National Natural Science Foundation of China under Grant Nos.49574237 and 49774247.
文摘This paper presents the modified magnetohydrodynamic(MHD)model and simulations of solar wind-magnetosphere interactions.We use the two-dimensional and three-component,compressible,resistive,ion gyroviscous and Hall MHD model,i.e.,including the ion Unite Larmor radius(FLR)and Hall MHD effects,but neglecting the electron inertia and electron FLR effects.The composed dynamic pressure pulses(shear variations in the How velocity)in the solar wind form gusts that continually buffet the magnetosphere and cause the time-dependent magnetic reconnection at the magnetopause.The results show that the magnetic Held and the How velocity components perpendicular to the reconnection plane can be generated in magnetopause current layer.The vortical How structures can also occur in the magnetospheric side region.These results are responsible for non-ideal MHD properties of the plasma fluid,i.e.,ion FLR and Hall MHD effects.