The results of experimental studies of the hydrodynamics of the model coolant flow at the entrance to the VVER-1000 core support grid are presented. A 1:17 scale model of the in-reactor pressure path was built, which allowed physical modeling of the conditions for coolant flow entry into the core by installing support risers. A method was developed for measuring the flow velocity distribution at the entry into the core. Experimental studies of the hydrodynamics of the water flow before entry into the core for versions with and without support risers were performed on a model of the VVER-1000 pressure path. Experimental data were obtained on the influence of the operating regime of the reactor cooling loops and the geometric dimensions of the elliptical collector between the vessel bottom and the perforated bottom of the shaft on the uneven distribution of the coolant flow rate at the entry into the core.