The Effects of Scalloping Width and Position on Jet Mixing of Lobed Nozzles

Abstract

A series of geometric models of lobed nozzles with a central plug was created by different scalloping positions and widths. The shapes of lower and upper edges, cutting depth were kept unchanged. In this study, by the use of numerical simulation, the effects of scalloped width and position on the performance of jet mixing in the pumping condition were analyzed. The results indicated that, as the position of scalloped lower edge kept constant, the radial position of the accelerated mixing region of sidewalls did not change. The accelerated mixing region is enlarged as scalloped width increased, while the growth rate of enlarged region is less than the growth rate of scalloping width. When the scalloped region with the same width moved outward in the radial direction, the mixing rate of the region of the lobe outer edges increased. However, the distance for complete mixing of the primary stream in the core region was increased. It was also found that inward moving of scalloped lower edge enhanced the effect of strengthening streamwise vortices but induced more pressure loss.

The Effects of Spoilers on Jet Mixing of Lobed Nozzles

“…Energy equation was involved in the simulation. The same numerical simulation of jet mixing of lobed nozzle with the Fluent software packages has been used and validated in previous studies (Sheng et al 2014;Sheng et al 2015a;Sheng et al 2015b;Liu et al 2015). In order to analyze the mixing of lobed nozzle more clearly, an illustration of the tailing-edge of the lobed nozzle and the downstream regions (Sheng et al 2015b) is shown in Fig.…”

“…3 (Liu et al 2015). Owing to the complex geometry, tetrahedral cells are used to discretize the simulation domain.…”