A computational analysis of an annular converging-diverging (CD) and an altitude adaptive expansion-deflection (ED) nozzle is presented. Numerical results were generated using a 2D axisymmetric, pressure-coupled solver in conjunction with the Spalart-Allmaras turbulence closure model and second order spatial discretisation schemes. Results were recorded over a theoretical altitude range and com...

This paper presents the design and characterization of micro-fabricated 0.5 MHz silicon-based ultrasonic nozzles. Each nozzle is made of a piezoelectric drive section and a silicon-resonator consisting of five Fourier horns, each with half wavelength design and twice amplitude magnification. Results of impedance analysis and measurement of longitudinal vibration confirmed the simulation results...

A model of a submerged angular cavitation nozzle is established, which consists contraction part, parallel middle and expansion part. Based on the CFD technique, numerical simulation flow field carried out, in multiphase mixture model, renormalization group (RNG) k-ε turbulence are applied. Considering influence density cavitation, effects inlet outlet part velocity vapor volume fraction studie...

During the steel continuous casting, submerged entry nozzle (SEN) plays a crucial role in fluid characteristic of steel, which further affects slab quality. In this paper, model is developed to study influences inclination, area ratio, and side hole aspect ratio on steel. The results show that when angle increased from 10° 20°, impact points narrow surface were 0.402 m, 0.476 0.554 m away menis...

The presence of tones in the acoustic far field isothermal round jets for angles relative to flow direction is investigated Mach numbers between and 2 based on data from both experiments large-eddy simulations. For all numbers, as observed jet near-nozzle region previous studies, peaks are found far-field pressure spectra regardless nozzle-exit boundary-layer properties. They emerge near cutoff...

A nozzle conŽ guration for the production of an intense and collimated supersonic cluster beam is presented and characterized by numerical modeling. A simple lens added to a cylindrical nozzle exploits aerodynamic focusing effects. The effect of the focalizing nozzle is an enrichment of the core of the jet with clusters of an arbitrary size interval depending on carrier gas pressure and tempera...

In a continuing effort to study the mixing enhancement by large-scale streamwise vortices generated by a lobed nozzle, a high-resolution stereoscopic particle image velocimetry ~PIV! system was used in the present study to conduct three-dimensional measurements of air jet flows exhausted from a lobed nozzle and a conventional circular nozzle. The three-dimensional instantaneous and ensemble-ave...

BACKGROUND In combined proton-carbon fixed-nozzle treatment facilities with raster scanning delivery, the scattering of proton pencil beams caused by nozzle elements and the relatively large nozzle-to-isocenter distance cause a beam broadening. This may pose limitations to the achievable dose conformity. One way to counteract this effect is by delivering the treatment in a position closer to th...

This work aims to study the characteristics of multi-nozzle spray cooling using CFD method based on the fundamentals of air flow and liquid droplet collision dynamics. A mathematical model for the two-phase flow was presented. The simulations were performed using a EulerianeLagrangian approach. Focus was placed on revealing the flow behavior with multiple nozzles, the droplet trajectory, and th...

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