The universal growth of magnetic energy during the nonlinear phase of subsonic and supersonic small-scale dynamos
By analyzing a large ensemble of simulations across subsonic to supersonic regimes, this study reveals that while the nonlinear growth rate of small-scale dynamos varies from linear to quadratic depending on flow compressibility, the process consistently converts a fixed fraction of turbulent kinetic energy into magnetic energy over a characteristic duration of approximately 20 outer-scale turnover times.