The discussion centers on calculating pressure drop in fuel assemblies, specifically in pressurized water reactors (PWRs) with single-phase flow. Key factors influencing pressure drop include the frictional drop from fuel bundles, relative roughness of fuel rods, Reynolds number, and hydraulic diameter. The complexity of these calculations often necessitates empirical measurements in hydraulic loops rather than theoretical calculations. The significance of the "p/D" ratio in triangular lattice configurations within steam generators is also highlighted as a critical aspect of the analysis.
PREREQUISITESMechanical engineers, nuclear engineers, and researchers focused on fluid dynamics in nuclear reactor systems, particularly those involved in pressure drop analysis in fuel assemblies.
Thank you very much for such a kind response,Michal Kovac said:Hi, you wrote about pressure drop in fuel assemblies. But you have to specify, whether you mean pressurized water reactors (single phase flow) or boiling water reactors (two-phase flow).
In general, total fuel assembly pressure drop is formed by fuel bundle frictional drop (dependent on relative roughness of fuel rods, reynolds number, hydraulic diameter etc.) and other pressure drops of structural elements (top and bottom nozzle, spacing grids or mixing grids).
In general, it is not so simple to calculate pressure drops in fuel assemblies (especially the spacing grids) and it belongs to key know-how of certain fuel manufacturer. Mostly, pressure drops are measured in experimental hydraulic loops, rather than calculated.
If you want to know more, specify your problem. Here are some valuable sources:
Frictional losses - single phase
Pressure drop - two-phase