The Thermal-Hydraulic Calculation in a Fuel Cartridge When the Symmetry of Fuel Rods Packing Is Broken

Abstract

In the work, the problem of convective heat transfer in the fuel cartridge with fuel rods, including the case of broken symmetry in the packing of rods, is solved with new design tools of the R-functions method and the program complex POLYE. The developed design tools for constructing the equations of the boundaries of domains with translational and cyclic types of symmetry made it possible to significantly reduce the quantity of operations with a subsequent automation of this process, and, consequently, to reduce the time for solving problems. Problems are solved by a variational-structural method. The paper considers the influence of only one rod that breaks the symmetry of the packing, when it is located either in the central or in the peripheral zone of the cartridge, both with keeping the whole bundle parallel and with the rod’s curvature. In the presence of several ”non-standard” rods, it is also important to calculate the temperature field for the cartridge as a whole. Working with the mathematical model of the process and the computational experiment make it possible to study the properties and behavior of the process in various situations without serious consequences, relatively quickly and without significant expenditure.