Controlled electric field-assisted jetting from viscous and nanosuspension media droplets.
243 - 250.
This paper reports a study into forming a jet-on-demand to continuous microthreads by subjecting electric fields on high viscosity and low conducting media (concentrated nanosuspensions and dielectric mediums) droplets, placed on a conducting copper plate, which has a similar plate above at a distance of similar to 10 mm. The media used in this investigation has a viscosity >> 1000mPa s and an electrical conductivity << 10(-6) Sm-1 and in the case of nanomaterial loading in suspension is > 15 wt.%. The investigation illustrates both the ability to form jets in this configuration and the importance of the volume of media placed as a droplet which has a direct result on the formation of a jet subsequently fragmentating to droplets. At a droplet volume of < Q(0), the resting droplet when under the influence of an applied electric field deforms forming a cone, much like those referred to as the "Taylor Cones". On increasing the volume of the droplet to Q(0) and applying a voltage of similar to 4.6 kV across the plates, the apex of the cone was observed to pulsate. On further increasing the applied voltage, giving rise to an electric field strength of similar to 0.55 kV/mm, the pulsating apex stabilizes to evolve a stable jet which undergoes instabilities promoting the generation of droplets. Consequently, a fine jet-on-demand is obtained. On increasing the droplet volume to > Q(0), forms jets on both plates. The study elucidates the importance of this jetting approach for forming droplet relics containing self-assembled nanoparticles to continuous microthreads from concentrated nanosuspensions and dielectric media for forming structures by deposition that are most useful and have widespread applications in materials science and engineering. Hence, the physical behavior of this droplet deformation jetting - forming droplets under an imposed field, outlines the discussion presented in this paper.
|Title:||Controlled electric field-assisted jetting from viscous and nanosuspension media droplets|
|Keywords:||jet-on-demand, microthreading, self-assembly, nanosuspension, nanofabrication, CONE-JET MODE, SCALING LAWS, ELECTROSPRAY, LIQUIDS, ATOMIZATION, GENERATION, SIZE|
|UCL classification:||UCL > School of BEAMS > Faculty of Engineering Science
UCL > School of BEAMS > Faculty of Engineering Science > Mechanical Engineering
Archive Staff Only