Instability of MHD-modified interfacial gravity waves revisited
نویسندگان
چکیده
We reveal the basic mechanism of instability of the two-layer conductive fluid system carrying a normal current and exposed to a uniform external magnetic field. This process is a reflection of a MHD-modified interfacial gravity wave from the boundary. Due to special boundary conditions, the reflection coefficient turns out to be greater than 1 for some directions of the wave propagation. We consider two cases: reflection of a monochromatic plane wave from the plane boundary and reflection of rotating waves in a circular geometry. We believe that the proposed mechanism gives a new understanding of the instability formation in the system ‘liquid metal–electrolyte’ type. 2001 Elsevier Science B.V. All rights reserved. PACS: 03.40.Gc; 03.40.Kf; 68.10.-m
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