  We calculate elliptic and triangular flow parameters of thermal photons using
an event-by-event hydrodynamic model with fluctuating initial conditions at
200A GeV Au+Au collisions at RHIC and at 2.76A TeV Pb+Pb collisions at the LHC
for three different centrality bins. The photon elliptic flow shows strong
centrality dependence where $v_2(p_T)$ increases towards peripheral collisions
both at RHIC and at the LHC energies. However, the triangular flow parameter
does not show significant dependence to the collision centrality. The elliptic
as well as the triangular flow parameters found to underestimate the PHENIX
data at RHIC by a large margin for all three centrality bins. We calculate
$p_T$ spectrum and anisotropic flow of thermal photons from 200A GeV Cu+Cu
collisions at RHIC for 0--20\% centrality bin and compare with the results with
those from Au+Au collisions. The production of thermal photon is found to
decrease significantly for Cu+Cu collisions compared to Au+Au collisions.
However, the effect of initial state fluctuation is found to be more pronounced
for anisotropic flow resulting in larger $v_2$ and $v_3$ for Cu+Cu collisions.
We study the correlation between the anisotropic flow parameters and the
corresponding initial spatial anisotropies from their event by event
distributions at RHIC and at the LHC energies. The linear correlation between
$v_2$ and $\epsilon_2$ is found be stronger compared to the correlation between
$v_3$ and $\epsilon_3$. In addition, the correlation coefficient is found to be
larger at LHC than at RHIC.
