in EV-SHGM with and without the effect of flow to understand the increase in $E_{T}/N_{ch}$ from RHIC to LHC. Figure 13 demonstrates the $N_{part}$ dependence of average transverse momentum ($\langle p_{T} \rangle$) of charged hadrons at top RHIC and LHC $\sqrt{s_{NN}}$ = 2.76 TeV energies. The lines are model calculations and symbols are the experimental data [@Adams:2004cb; @Abelev:2013bla]. We find that, there is an almost 63% increase in $\langle p_{T} \rangle$ from top RHIC to LHC at 2.76 TeV energy in EV-SHGM model with collective flow. We also get an almost 57% increase in $\langle \beta_{r} \rangle$ from top RHIC to LHC at 2.76 TeV, which could be the reason for increase in $\langle p_{T} \rangle$. Further, no change in $\langle p_{T} \rangle$ is observed in a static SHGM model from RHIC to LHC. This is because a static SHGM uses T and $\mu_{B}$ as the inputs for the estimation of various thermodynamical observables. From top RHIC to LHC energies T and $\mu_{B}$ are found to be constant within systematics [@Abelev:2012wca]. This reveals that the increase in $E_{T}/N_{ch}$ at LHC could be explained by the increase in $\langle p_{T} \rangle$ and the collective flow. Here, we take all the hadrons 