  Chiral Magnetic Effect (CME) is the macroscopic manifestation of the
fundamental chiral anomaly in a many-body system of chiral fermions, and
emerges as anomalous transport current in hydrodynamic framework. Experimental
observation of CME is of great interest and significant efforts have been made
to look for its signals in heavy ion collisions. Encouraging evidence of
CME-induced charge separation has been reported from both RHIC and LHC, albeit
with ambiguity due to potential background contributions. Crucial for
addressing such issue, is the need of quantitative predictions for both CME
signal and the non-CME background consistently, with sophisticated modeling
tool. In this contribution we report a recently developed Anomalous Viscous
Fluid Dynamics (AVFD) framework, which simulates the evolution of fermion
currents in QGP on top of the data-validated VISHNU bulk hydro evolution. In
particular, this framework has been extended to event-by-event simulations with
proper implementation of known flow-driven background contributions. We report
quantitative results from such simulations and evaluate the implications for
interpretations of current experimental measurements. Finally we give our
prediction for the CME signal in upcoming isobaric collisions.
