Image Number 7 for United States Patent #4793966.
A nuclear reactor in which rupture by fatigue of the components of the control-rod assemblies is precluded. The fatigue is caused by the vibration of the components or cavitation under the action of the coolant flowing at a high velocity transversely to the control-rod assemblies. A perforated shroud is provided between the control rod assemblies and the outlet nozzles. The shroud distributes the transversely-flowing coolant over a large volume so that its velocity is substantially lower than the resonant velocity at which vibrations of substantial amplitude of the components or cavitation is produced.