STG-17 Annular distributors: A parametric design study

K. J. Farrell
2005; rev 09/2015

Unlike exchangers with conventional nozzles and nozzles with impingement devices, heat exchangers with annular distributors utilize full tube bundles while increasing end zone effectiveness and reducing the pressure drop and tube vibration potential. The uniformity of flow at the bundle entrance is controlled by the size and geometric aspect ratio of the flow areas in the distributor belt and the relative position and sizes of the slots in the shell. Using computational fluid dynamics (CFD) simulations, we compare the results of a parametric study of inlet annular distributors. The maximum velocity through the slot is substantially higher than the ideal velocity calculated by applying the one-dimensional continuity equation. Our conclusion, based on flow uniformity and total pressure loss, is that multiple slots with large expansion area ratios in symmetric arrangements are more desirable than conventional nozzles.