The bypass dual throat nozzle (BDTN) is a new kind o f fluidic vec toring nozzle. A bypass is set between the upstream convergent section and upstream minimum area based on the conventional dual throat nozzle (DTN). The BDTN shows a minimum or even no penalty on the nozzle's thrust performance, while it would be able to produce steady and efficient vectoring deflection similar to the conventional DTN. A BDTN model has been designed and sub jected to experimental and computational study. The main results show that: (1) BDTN does not consume any secondary injection from the other part of the engine, while it can produce steady and efficient vectoring deflection. (2) Under the same condition, it can provide the maximum thrust vectoring efficiency o f all the known fluidic thrust vectoring concepts reported in the literature. (3) The thrust vector angle is also greater than that of the conventional DTN that has been reported up to now. Especially, under NPR = 10, the thrust vector angle o f BDTN can reach 21.3 deg. (4) For a wide NPR range from 2 to 10, the BDTN generates the best thrust vectoring performance under NPR =4. Above all, the BDTN is well suited to produce vectored thrust for nozzles.

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Kanbara Reactor (KR) is widely used for hot metal desulfurization pretreatment in the steelmaking industry. The configuration of its impeller plays a crucial role in the reactor performance, but its function is not fully understood. Herein, a 3D volume of fluid (VOF) model coupled with the sliding mesh technique is developed, and the performance of five impellers with different dimensions is investigated. After the test of grid dependency, the calibration of turbulent models, and the validation via experiments, the numerical model is applied to study the typical developing phenomena and the effect of impeller dimension on the fluid flow characteristics, mixing time, interface profile, and vortex core depth. The results show that the centrifugal discharging flow extruded by the rotating impeller creates a double‐recirculation flow pattern in the axial direction. When the aspect ratio χ of the impeller increases, the upper recirculating region is successively strengthened and enlarged. Furthermore, the mixing time as a function of impeller configuration exists a minimum value. Impeller III is the optimal configuration in the current study. In addition, the relationship between vortex core depth and χ is obtained, and the velocity of the gas–liquid interface increases with the increase in χ.

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