We performed numerical simulations of two-dimensional magnetohydrodynamic (2D MHD) turbulence on an ${8192}^2$ grid with mean magnetic fields $B_0=0,1$, 3, 6, and 10. The energy spectra and fluxes of Elsässer variables are in better agreement with Kolmogorov-like phenomenology ($k^{-5/3}$) than Iroshnikov-Kraichnan phenomenology ($k^{-3/2}$). Our numerical study shows that $k_{\parallel }\propto k_{\perp }$ for all $B_0$, which is contrary to the predictions of “critical balance.” Additionally, the averaged alignment angle between the velocity and magnetic fluctuations remains constant across all length scales, contrary to the predictions of dynamic alignment. These results indicate that local alignment and antialignment events coexist but statistically balance each other, leading to an overall absence of scale-dependent alignment. Thus, our results demonstrate violations of both critical-balance and dynamic alignment in 2D MHD turbulence. We explore regimes up to $B_0/\delta b\approx 10$, over which $k^{-5/3}$ spectral scaling is observed, relevant to solar-wind turbulence near 1 AU and beyond.

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• Magnetohydrodynamic turbulence
• Magnetohydrodynamics
• Turbulence