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تسجيل مستخدم جديدEndeavors in the DualSPHysics code to evaluate heat transfer in nuclear systems
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This article condenses current endeavors and improvements in the expansion of applications of the DualSPHysics code to analyze heat transfer in a nuclear reactor core. This includes the essential conservation equations and certain physical considerations, particularly the thermal conductivity variable model, considering changes in the reference density to maintain the accuracy in the solution. Conventionally, to study these sorts of systems, Eulerian methods have been developed, nevertheless, this kind of method based on well-defined mesh shows major restrictions. The DualSPHysics code, based on Smoothed Particle Hydrodynamics (SPH) technique, has shown to be a real and robust alternative since it involves a free mesh approach, and the numerical method is very well parallelized in both computational and graphical process units (CPU and GPU). The results for the improvements developed in the present work show an exceptionally good approximation with other simulation approaches and also with experimental observation in the three cases studied (1) heat transfer analysis in a bidimensional system with thermal conductivity coefficient k variable, (2) natural convection heat transfer in a horizontal cylindrical ring similar to the space between the fuel rod and the cladding and (3) heat transfer in an experimental nuclear fuel rod square arrangement like in a Pressurized Water Reactor (PWR) nuclear core. Enhancements to this code (DualSPHysics) to use it in nuclear applications are fundamental in the exploitation of this technique in crucial areas of study.
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