The droplet dynamics and collisions after a liquid jet breakup have been experimentally studied in low gravity conditions. An experimental setup was designed in order to be used at the I.N.T.A. Drop Tower, which allows for 2.1 seconds of microgravity. The dynamics of distilled water jets injected into a rectangular tank was recorded by means of a high-speed video camera. Observations of the dro...

Droplet transport processes that occur in fuel sprays and spray flames were examined using laser velocimetry, phase Doppler interferometry, and laser sheet beam photography. Droplet size and velocity (axial and radial) distributions were obtained in a swirl-stabilized, pressure-atomized kerosene spray under nonburning and burning conditions. The results show that the introduction of swirl to th...

The characteristics of fluid flow and phase separation in an oil-water separator were numerically analysed as part of the work presented herein. Simulations were performed for different velocities and droplet diameters, and the way this parameters can influence the separator geometry was studied. The simulations were carried out using the software package Fluent 6.2, which is designed for numer...

This paper experimentally investigates the mechanism of water droplet detachment in a confined microchannel under highly inertial (10<Re< 200) air flow conditions. Experimental observations show that as the Reynolds number of the continuous phase is increased, the droplet transitions from an elongated slug to a nearly uniform aspect ratio droplet. Supporting scaling arguments are then made that...

The Ranque–Hilsch vortex tube (RHVT) is a device currently used to generate local cooling. In general, the fluid that is injected into the RHVT is a single-phase gas. In this study, however, we have added a dispersed phase (water droplets) to the gas (nitrogen). By means of phase Doppler particle analysis, three velocity components, their higher order moments, and sizes of droplets were measure...

In the present work, an investigation of stagnation flow imposed on a supercooled water drop in cold environmental conditions was carried out at various air velocities ranging from 0 (i.e., still air) to 10 m/s along with temperature spanning from −10 to −30 ◦C. The net effect of air flow on the impacting water droplet was investigated by controlling the droplet impact velocity to make it simil...

Droplets are frequently observed to move as if they were solid rather than liquid, i.e., with no slip at the liquid-liquid interface. This behavior is usually explained in terms of the so-called “stagnant cap” model, in which surfactants accumulate at the trailing edge of the droplet, immobilizing the surface and increasing the observed drag coefficient. Here, we show that the drag coefficient ...

Abstract The present study aims at characterizing the atomization of a water jet which is injected at high velocity into still air thanks to an industrial nozzle particularly used in irrigation. The nozzle diameter is 4.36 mm and exit velocity is about 25 m/s. The droplet size and velocity are analyzed by a double-pulsed shadowgraph imaging technique using a Droplet Tracking Velocimetry (DTV) m...

In this paper, the authors proposed a novel idea of a long-reach flying inkjet system employing electrostatically-accelerated ink drop for the purpose of functional ink micro pattern plotting by contact-free and environment friendly. Proposed working principle was demonstrated through experiment and analysis. At the 5-mm of electrode gap and φ 120 m μ of nozzle, the applicable maximum voltage w...

This paper aims to investigate a mechanism of microdroplet formation at a micro T-shaped junction using a “phaselocked multicolor confocal micro-PIV (Particle Image Velocimetry)” technique[1]. The multicolor system can measure dynamic behavior of each phase of multiphase flow separately and simultaneously. Additionally, the phase-locking technique enables picking up same condition of droplet fo...