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arXiv · 0907.3571

The third-order law for increments in magnetohydrodynamic turbulence with constant shear

M. Wan·S. Servidio·S. Oughton·W. H. Matthaeus
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Abstract

We extend the theory for third-order structure functions in homogeneous incompressible magnetohydrodynamic (MHD) turbulence to the case in which a constant velocity shear is present. A generalization is found of the usual relation [Politano and Pouquet, Phys. Rev. E, 57 21 (1998)] between third-order structure functions and the dissipation rate in steady inertial range turbulence, in which the shear plays a crucial role. In particular, the presence of shear leads to a third-order law which is not simply proportional to the relative separation. Possible implications for laboratory and space plasmas are discussed.

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M. Wan, S. Servidio, S. Oughton, W. H. Matthaeus. 2009-07-21. The third-order law for increments in magnetohydrodynamic turbulence with constant shear. https://doi.org/10.1063/1.3240333

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