Nonlinear Processes in Geophysics www.nonlin-processes-geophys.net 1023-5809 1607-7946 14 4 2007 10.5194/npg-14-351-2007 http://www.nonlin-processes-geophys.net/14/351/2007/ http://www.nonlin-processes-geophys.net/14/351/2007/npg-14-351-2007.html http://www.nonlin-processes-geophys.net/14/351/2007/npg-14-351-2007.pdf 351 359 2007-07-06 Three-dimensional simulations of turbulent spectra in the local interstellar medium D. Shaikh dastgeer@ucr.edu G. P. Zank Institute of Geophysics and Planetary Physics, University of California, Riverside CA 92521, USA Three-dimensional time dependent numerical simulations of compressible magnetohydrodynamic fluids describing super-Alfvénic, supersonic and strongly magnetized space and laboratory plasmas show a nonlinear relaxation towards a state of near incompressibility. The latter is characterized essentially by a subsonic turbulent Mach number. 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