Comparison of the numerical results of our model with Fong et al. (2016) and Nakar & Piran (2011). The left panel is the evolution of the bulk Lorentz factor of the ejecta; the right panel is the radio lightcurves at 6 GHz. The same values for the physical parameters have been adopted to ensure a uniform comparison. The black hole model has a total kinetic energy E_k = 10⁵⁰ erg.