one of the most common methods for controlling and increasing maneuverability of projectiles, especially the ones which move at high altitude and in low density air, is using lateral or reaction jets. the resultant force of the reaction jet is related to the jet and flow parameters. for finding their relation experimental, numerical, and analytical methods have been used. in order to change the...

Cold spraying is a coating process which enables production of metallic and metallic ceramic coatings with dense (very low porosity level) and pure (low oxygen content) structures. Several coating applications such as corrosion resistance and electrical conductivity rely on these properties. Generally, cold spraying is based on higher particle velocities and lower process temperatures than othe...

Nozzle clogging is a serious productivity and quality problem in continuous casting. This work reviews the causes, effects, and solutions to clogging in continuous casting nozzles. The results of a one-dimensional, steady state analysis of the heat loss from the molten steel stream through the nozzle wall are discussed. The analyses show that steel may freeze within the clog matrix for a relati...

The yield of flow cytometric sorted Xand Y-chromosome-bearing sperm in a given time period is an important factor in the strategies used for fertilization and the production of sex-preselected offspring. This yield is dependent on the efficiency with which the modified flow cytometer/cell sorter analyzes the DNA of spermatozoa. The efficiency is directly related to the number of sperm with the ...

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 ...

This study is designed to consider the two important yet often neglected factors, which are factory recommendation and bit features, in optimum bit selection. Image processing techniques have been used to consider the bit features. A mathematical equation, which is derived from a neural network model, is used for drill bit selection to obtain the bit’s maximum penetration rate that corresponds ...

Experiments on the onset of buoyant instabilities leading to periodic formation of vortical structures in planar buoyant plumes of helium and helium/air mixtures injected into quiescent air are reported for a range of nozzle widths (w520– 70 mm), plume fluid densities ~pure helium to that approaching air!, and velocities at the nozzle exit. First, the plume parameters corresponding to the onset...

the main purpose of this study is to introduce a new method for nanofibers by bulk layer production. in the present method the effect of some parameters including take-up velocity, applied voltage, polymer solution concentration on density of produced layers is investigated. the compression characteristic of nanofiber layers produced under optimum electrospinning is also investigated. it was sh...

Starting flow through a nozzle or orifice typically results in the transient formation of a leading vortex ring and trailing jet. Experiments are conducted to investigate the dynamics of this process in the case of a temporally variable nozzle exit diameter, with the aim of understanding these flows as they occur in Nature and emerging technologies. By kinematically decoupling the source flow f...