A nuclear reactor with a heavy liquid metal coolant, with, located in the same vessel, at least one heat exchanger or at least one steam generator, control and monitoring elements, one circulation pump of the primary circuit, main channels and auxiliary channels, designed for the coolant flow, that do not perform the function of core cooling, including a header for collecting and distributing the coolant through the main and auxiliary channels, characterized in that in the in-vessel space of the nuclear reactor, not occupied by these elements, containers are placed with gaps, providing the coolant flow, wherein the said containers are filled with a material that reflects or absorbs neutrons, with a heat capacity greater than that of the coolant, wherein the said containers are placed in such a way that the resulting gaps form channels with a turbulent coolant flow for cooling these containers at its flow rate corresponding to the nominal power level of the nuclear reactor.