Use of jet cavitation, however, occurs through an exit nozzle whose diameter can be changed, thereby changing volume with changing velocity. The results of such a change is shown to tie cavitation damage more powerfully to volume flow than to velocity. A specific example is in cavitation erosion of a high strength igneous rock which remained virtually undamaged at 70 MPa driving pressure but wa...

A continuous near-field electrospray process has been developed to deposit micropatterns. Different from traditional electrospray technologies, the nozzle-to-substrate distance was shortened to less than 5 mm, and a glass capillary nozzle with a diameter of tens of microns was used. Steady and continuous ejection was achieved, and patterns with line widths of sub-100 μm were generated. The infl...

Waterjet breakup is traditionally considered to follow the Ohnesorge classification. In this classification, high Reynolds number waterjets are considered to atomize quickly after discharge. By generating a constricted waterjet where the water flow stays detached all the way through the nozzle, we have observed the first wind-induced breakup mode at high Reynolds numbers. Such a peculiar behavi...

Numerical studies have been carried out using a validated two-dimensional RNG k-epsilon turbulence model for the design optimization of a thrust vector control system using shock induced supersonic secondary jet. Parametric analytical studies have been carried out with various secondary jets at different divergent locations, jet interaction angles, jet pressures. The results from the parametric...

Experimental investigation to study the heat transfer between a vertical round alumina-water nanofluid jet and a horizontal circular round surface is carried out. Different jet flow rates, jet nozzle diameters, various circular disk diameters and three nanoparticles concentrations (0, 6.6 and 10%, respectively) are used. The experimental results indicate that using nanofluid as a heat transfer ...

Direct ink writing (DIW) has demonstrated great potential as a multimaterial multifunctional fabrication method in areas as diverse as electronics, structural materials, tissue engineering, and soft robotics. During DIW, viscoelastic inks are extruded out of a 3D printer's nozzle as printed fibers, which are deposited into patterns when the nozzle moves. Hence, the resolution of printed fibers ...

Cryogen spray cooling allows removing large amounts of heat in short periods of time. Previous investigations have shown that stainless steel wire meshes placed between spray nozzle and target surfaces effectively increase uniformity in lateral heat extraction while reducing cooling efficiency. In this study we used phase Doppler particle analysis to assess the effect of a wire mesh on the diam...

Article history: Received: 09.06.2015. Received in revised form: 01.10.2015. Accepted: 08.10.2015. Liquid nitrogen is expected to be used as a jet medium in petroleum engineering because of its cryogenic and non-polluting characteristics. To identify the velocity distribution characteristics of liquid nitrogen jet, a computational fluid dynamics model was built by coupling the equations for nit...

Visualization study of bubble growth with multiple tangential nozzles is investigated in a bubble absorber. Bubble behavior is studied with different flowing condition like still, co-current and counter-current flow of water. Effect of air flow rate, water flow rate, nozzle diameters, number of nozzles and orientation of nozzle angle with reference to vertical plane on bubble diameter is studie...

BACKGROUND AND OBJECTIVES Cryogen spray cooling (CSC) is used for epidermal protection during laser dermatologic surgery. However, further research is necessary to optimize the use of CSC for many applications, particularly in patients with darker skin types, and in procedures with deep-targeted chromophores. STUDY DESIGN/MATERIALS AND METHODS With the objective to enhance cryogen spray atomi...