Consequences of fluctuating microscopic conductivity in mean-field electrodynamics of turbulent fluids are formulated and discussed. If the conductivity fluctuations are assumed to be uncorrelated with the velocity fluctuations then only the turbulence-originated magnetic diffusivity of the fluid is reduced and the decay time of a large-scale magnetic field or the cycle times of oscillating turbulent dynamo models are increased. If, however, the fluctuations of conductivity and flow in a certain well-defined direction are correlated, an additional diamagnetic pumping effect results, transporting the magnetic field in the opposite direction to the diffusivity flux vector $\langle \unicode[STIX]{x1D702}^{\prime }\boldsymbol{u}^{\prime }\rangle$ . In the presence of global rotation, even for homogeneous turbulence fields, an alpha effect appears. If the characteristic values of the outer core of the Earth or the solar convection zone are applied, the dynamo number of the new alpha effect does not reach supercritical values to operate as an $\unicode[STIX]{x1D6FC}^{2}$ -dynamo but oscillating $\unicode[STIX]{x1D6FC}\unicode[STIX]{x1D6FA}$ -dynamos with differential rotation are not excluded.

中文翻译：

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具有波动电导率的湍流流体的电动力学

制定和讨论了湍流平均场电动力学中波动的微观电导率的后果。如果假设电导率波动与速度波动不相关，那么只有流体的湍流引起的磁扩散率会降低，大尺度磁场的衰减时间或振荡湍流发电机模型的周期时间会增加。然而，如果电导率的波动和在某个明确定义的方向上的流动相关，则会产生额外的反磁泵浦效应，将磁场沿与扩散通量矢量相反的方向传输 $\langle \unicode[STIX]{x1D702}^{\prime }\boldsymbol{u}^{\prime }\rangle$ . 在存在全局旋转的情况下，即使对于均匀湍流场，也会出现阿尔法效应。如果应用地球外核或太阳对流区的特征值，新阿尔法效应的发电机数不会达到超临界值，可以作为 $\unicode[STIX]{x1D6FC}^{2}$ -发电机但振荡 $\unicode[STIX]{x1D6FC}\unicode[STIX]{x1D6FA}$ - 不排除带差速旋转的发电机。