Computational Fluid Dynamics Approach to Evaluate Jet Impingement Loads Due to Rupture of High Energy Pipes in Nuclear Reactors

Abstract Accurate evaluation of jet impingement loads due to pipe ruptures is crucial for nuclear power plant design and safety analysis. These loads can cause catastrophic damage to neighboring components. Although jet impingement models exist in the literature, additional effort is required to overcome their inaccuracy and non-conservatism. In the current study, an evaluation of the jet impingement loads due to a full guillotine rupture in a high energy pipeline is investigated using Computational Fluid Dynamics (CFD). The model represents a higher fidelity approach to better assess the postulated pipe rupture and its effect on neighboring pipelines. Specifically, a 3D multiphysics ANSYS Fluent model is developed to simulate the rupture of the selected pipes. The model accounts for the multiphase nature of the problem by including heavy water liquid, heavy water vapor, and surrounding air. Moreover, the model accounts for a number of highly coupled physical processes including turbulence, multiphase interactions, flashing, and heat transfer. The results show that the model can accurately predict the jet behavior and characteristics. Additionally, the results indicate a direct relationship between the diameter of the ruptured pipe, rupture area, and the magnitude of impingement loads. Specifically, larger diameters and rupture areas correlate with increased jet impingement loads, while greater distances between pipes result in decreased loads. These observations are pivotal for designing robust systems capable of withstanding varied impingement scenarios.