  Externally driven interstellar turbulence plays an important role in shaping
the density structure in molecular clouds. Here we study the dynamical role of
internally driven turbulence in a self-gravitating molecular cloud core.
Depending on the initial conditions and evolutionary stages, we find that a
self-gravitating core in the presence of gravity-driven turbulence can undergo
constant, decelerated, and accelerated infall, and thus has various radial
velocity profiles. In the gravity-dominated central region, a higher level of
turbulence results in a lower infall velocity, a higher density, and a lower
mass accretion rate. As an important implication of this study, efficient
reconnection diffusion of magnetic fields against the gravitational drag
naturally occurs due to the gravity-driven turbulence, without invoking
externally driven turbulence.
