Mixing characteristics of jet emerging from a subsonic nozzle exit has been experimented and the results are compared with Uncontrolled jet and controlled jet configurations. The mixing enhancement was achieved using a passive method of jet control in which tandem tabs arrangement with rectangular cross section are fixed at the nozzle exit. Two Tab configurations, the Tandem tab (TT) and Stepped Tandem Tab (STT) are used to enhance the mixing characteristics of the jet, the aspect ratio (length /width) of the tabs was 1.67 offering a blockage ratio of 9.55% to the nozzle exit. The blockage ratio of TT and STT configurations are maintained to be equal so that the mixing characteristics can be compared. The axial and radial jet spread are compared for nozzle exit Mach numbers of 0.6, 0.8 and 1.0. The TT controlled jet offered a potential core reduction of 63%, 78% and 82% for Mach numbers 0.6, 0.8 and 1.0 respectively. The STT controlled jet offered a potential core reduction of 89%, 90% and 85% for Mach numbers 0.6, 0.8 and 1.0 respectively. The radial spread of Uncontrolled jet, controlled jet with TT and STT are plotted at several X/D locations and found that the controlled jets have more jet spread in both radial directions. A simulation is conducted for jets with exit Mach number 0.8 and the results are validated with the experimental findings. Based on the preliminary experimentation and computation, the STT controlled jet achieved better jet mixing through more potential core reduction and radial spread characteristics as compared to the TT configuration and base nozzle.

This paper investigates the influence of a weak-jet on the development of a turbulent axisymmetric strong jet. A parametric study is carried out to evaluate simultaneously the effect to the jets-spacing (S/D=3 and S/D=7. 5) and their velocity ratios in range 0≤ λ ≤ 1. The mixing phenomenon is studied numerically by the finite volume method using the 3D-RANS second-order model, which gives a good agreement with the available data. Three distinct regions of this type of jets interaction are evidenced. This study confirms that the jets spacing affects strongly the converging region and has a minor effect on the combining region. It is found that the weak jet attracts the strong jet and the combining region extends from 30D to 40D where the self-similarity of a single jet is obtained. The jet width decreases when velocity ratio and jets spacing augment. In the combining region, in comparison with the free jet, it is found that the addition of a weak-jet increases the decay rate of the centerline velocity.

Median arcuate ligament syndrome (MALS) is a rare benign condition typically affecting young females. It usually presents with chronic abdominal pain, nausea, vomiting and weight loss. They are usually diagnosed incidentally on MDCT angiography. We report a rare adult male of MALS which presented with a recurrent hypertensive urgency without any abdominal pain leading to an extensive workup and incidental diagnosis of MALS which was successfully treated by angioplasty with stenting of celiac trunk without any complication.