When the magnetic field deviates from potential or force-freefield, the field-aligned current can be produced, and it relates closely with the intensity and lifetime of ducts.
当磁场偏离势场或无力场时，将会产生场向电流，该电流与导管的强度和稳定维持密切相关。
2
With force free model, it is shown that the photospheric transverse current is independent of the sense of the transverse field and can be found completely by vector magnetographic measurement.
并证明了光球横向电流与横向磁场的指向无关，因而完全可以由向量磁象仪测定。
3
Using the multistep implicit scheme, a numerical study was made to reveal the influence of linear force-freefield to the spontaneous reconnection of current sheets.