Manipulation of Water Jet Trajectory by a Nonuniform Electric Field in Water Jet Material Processing

Abstract

In spite of its applications in macromanufacturing processes, water jet processing has not been extensively applied to the field of micromanufacturing owing to its poor tolerance and lack of effective control of the jet impingement position. This paper investigates the phenomenon of liquid dielectrophoresis (LDEP) using a localized nonuniform static electric field to deflect and control the jet's trajectory at the microscale for a water jet in air. A new analytical modeling approach has been attempted by representing the stable length of a water jet as a deformable solid dielectric beam to solve for the deflection of the jet under the action of the electric field. This method bypasses the complicated flow analysis of the water jet in air and focuses specially on the effect of the electric field on the trajectory of a laminar water jet within the working length. The numerical analysis of the phenomena for this electrode configuration was carried out using comsol. Preliminary proof-of-concept experiments were conducted on a 350 μm diameter sized water jet flowing at 0.6 m/s using a pin plate electrode configuration where a deflection of around 10 deg was observed at 2000 V. The results from the simulation are in good agreement with the results obtained in the preliminary experiments. This novel approach of modeling the water jet as a deformable dielectric beam might be useful in numerous applications involving precise control of the water jet's trajectory particularly in microwater jet material processing.

A Critical Review on the Sensing, Control, and Manipulation of Single Molecules on Optofluidic Devices

“…Figure 6b illustrates the details of a DEP-based particle separation method in a microfluidic device [288]. DEP is a phenomenon where a chargeneutral but polarizable particle experiences a force in a non-uniform electric field due to the interaction of the particle's dipole and the spatial gradient of the electric field [302][303][304][305]. Jason et al have demonstrated a methodology of particle separation based on DEP in a microfluidic device whose top and cross-sectional views are shown in Figure 6b(i,ii), respectively [288].…”

Response of High-Pressure Micro Water Jets to Static and Dynamic Nonuniform Electric Fields

“…The motion, deformation, and instability of charged liquid jets were examined by using a nozzle-ring electrode apparatus by Hokmabad et al [20]. A preliminary study on manipulating the trajectory of a low-pressure water jet with corresponding modeling in COMSOL was performed by Mohanty et al [21]. Furthermore, Jones discussed the possibility, capability, and applications of DEP liquid actuation at the microscale [22].…”