Determination of presheath lengths in magnetized plasmas by using fluid theories

The length of the presheath, L, due to an object in a magnetized flowing flowing plasma is scaled by a characteristic length Lll ; I.e., L = KLll = Ka2Cs/D, where a, Cs, and D are the size of the perturbing object, the ion acoustic speed (≡ √(ZTe + Ti)/mi), and the cross-field diffusivity, respectively. The scale factor K is calculated as a function of transport parameters, such as the drift velocity and the ratio of viscosity to diffusivity, by using fluid theories, and practical sizes of the presheaths, in terms of the density perturbation, are obtained from the analytical solutions of one-dimensional fluid models of the magnetized plasma