Analysis of deformation dynamics of droplet in oil under the CPG electric field

Abstract

Given that the common constant frequency pulse electric field cannot meet the requirements of the optimal demulsification frequency change in the demulsification process, a chaotic pulse group (CPG) electric field with chaotic group frequency, constant field intensity and group pulse number is proposed to excite all droplets in oil to resonate and improve the demulsification efficiency. However, the vibration and deformation characteristics of droplet in emulsion oil under the CPG electric field is unclear. Therefore, the droplet deformation dynamic model under the CPG electric field is established by applying the finite element method. The influences of duty cycle and group pulse number on droplet deformation are analyzed, and the mechanism of droplet relaxation in CPG electric field is investigated. Results show that the optimal duty cycle is 0.5 and the optimal group pulse number is 3. The droplet tends to be resonant when the frequency of the electric field group is close to its resonant frequency, and its steady vibration mainly depends on the consistency of the state of the droplet after the end of the latter pulse with that of the former pulse.