  We explore parton collisional effects on the conversion of geometry
eccentricities into azimuthal anisotropies in Pb+Pb collisions at
$\sqrt{s_{NN}}$ = 5.02 TeV using a multi-phase transport model. The initial
eccentricity $\varepsilon_{n}$ (n = 2,3) and flow harmonics $v_{n}$ (n = 2,3)
are investigated as a function of the number of parton collisions ($N_{coll}$)
during the source evolution of partonic phase. It is found that partonic
collisions leads to generate elliptic flow $v_{2}$ and triangular flow $v_{3}$
in Pb+Pb collisions. On the other hand, partonic collisions also result in an
evolution of the eccentricity of geometry. The collisional effect on the flow
conversion efficiency is therefore studied. We find that the partons with
larger $N_{coll}$ show a lower flow conversion efficiency, which reflect
differential behaviors with respect to $N_{coll}$. It provides an additional
insight into the dynamics of the space-momentum transformation during the QGP
evolution from a transport model point of view.
