The main objective of nuclear reactor safety is to maintain the nuclear fuel in a thermally safe condition with enough safety margins during normal operation and anticipated operational occurrences. In this research, core flow bypass is studied under the conditions of the unavailability of safety systems. As core bypass occurs, the core flow rate is assumed to decrease exponentially with a time constant of 25 s to new steady state values of 20, 40, 60, and 80% of the nominal core flow rate. | Thermal hydraulic analysis of core flow bypass in a typical research reactor Nuclear Engineering and Technology 51 (2019) 54e59 Contents lists available at ScienceDirect Nuclear Engineering and Technology journal homepage: Original Article Thermal hydraulic analysis of core flow bypass in a typical research reactor Said . Ibrahim a, Salah El-Din El-Morshedy b, Abdelfatah Abdelmaksoud b, * a Mechanical Engineering Department, Faculty of Engineering, Al-Azhar University, Cairo, Egypt b Reactors Department, Atomic Energy Authority, Cairo, Egypt a r t i c l e i n f o a b s t r a c t Article history: The main objective of nuclear reactor safety is to maintain the nuclear fuel in a thermally safe condition Received 17 April 2018 with enough safety margins during normal operation and anticipated operational occurrences. In this Received in revised form research, core flow bypass is studied under the conditions of the unavailability of safety systems. As core 24 July 2018 bypass occurs, the core flow rate is assumed to decrease exponentially with a time constant of 25 s to Accepted 29 August 2018 Available online 7 September 2018 new steady state values of 20, 40, 60, and 80% of the nominal core flow rate. The thermal hydraulic code PARET is used through these calculations. Reactor thermal hydraulic stability is reported for all cases of core flow bypass. Keywords: Thermalehydraulics © 2018 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the MTR reactors CC BY-NC-ND license (). Core flow bypass 1. Introduction transient correlations were developed. Housiadas [1] investigated the course of loss of flow transients in pool-type research reactors, Research reactors exist in many countries around the world. with SCRAM disabled. The analysis is performed with a customized Many countries consider
