  Active Region (AR) 12192 is the biggest AR observed in solar cycle 24 so far.
This was a long-lived AR which survived for four Carrington rotations (CR) and
exhibited several unusual phenomena. We measure the horizontal subsurface flows
in this active region in multiple rotation using the ring-diagram technique of
local helioseismology and the Global Oscillation Network Group (GONG+)
Dopplergrams, and investigate how different was the plasma flow in AR 12192
from that in AR 10486. Both regions produced several high M- and X-class flares
but had different CME productivity. Our analysis suggests that these ARs had
unusually large horizontal flow amplitude with distinctly different directions.
While meridional flow in AR 12192 was poleward that supports the flux transport
to poles, it was equatorward in AR 10486. Furthermore, there was a sudden
increase in the magnitude of estimated zonal flow in shallow layers in AR 12192
during the X3.1 flare, however, it reversed direction in AR 10486 with X17.2
flare. These flow patterns produced strong twists in horizontal velocity with
depth in AR 10486 that persisted throughout the disk passage as opposed to AR
12192, which produced a twist only after the eruption of the X3.1 flare that
disappeared soon after. Our study indicates that the sunspot rotation combined
with the re-organization of magnetic field in AR 10486 was not sufficient to
decrease the flow energy even after several large flares that might have
triggered CMEs. Furthermore, in the absence of sunspot rotation in AR 12192,
this re-organization of magnetic field contributed significantly to the
substantial release of flow energy after the X3.1 flare.
