Numerical study on swirl flow analysis of a modified dump combustor for different vane angles

Abstract A numerical study has been carried out on flow characteristics for turbulent swirl flow in a modified dump combustor with central restriction of vertical ellipsoidal (VE) dome shape. Here, four different swirlers with different vane angle (15°, 30°, 45° and 60°) have been considered. In this study, the flow is considered to be highly turbulent and accordingly, the value of Reynolds number is chosen as 1.2x105. The governing realizable k-ε model and Reynolds stress model (RSM) have been used to solve the turbulent parameters for the considered cases. The relevant governing differential equations for the conservation of mass and momentum have been solved by using SIMPLE algorithm with the commercial CFD code ANSYS Fluent 16.0. From the study, it is observed that width and strength value of recirculating zone increase with the increase of vane angle of swirler up to a certain value. Variation of axial and tangential velocities with radial distance at different locations, have been studied in details for considered four swirlers. Under turbulent swirl flow condition, 45° vane angle swirler is suitable to create both primary re-circulation zone before the restriction and secondary recirculation zone after the restriction.