Numerical Simulation and Analysis of the Vibration Characteristics of the String Vibration Screen Mesh

Abstract

With the deepening of oil and gas drilling, the increase of ultrafine particles and the complexity of waste water-based drilling mud have intensified the difficulty of solid-liquid separation. This paper addresses problems such as screen mud cake and clogging of fine mesh screens during the operation of drilling fluid vibrating screens. A novel string vibration-based detachment process is proposed, utilizing a single excitation source to induce string vibration in the filter screen. This promotes the detachment of filter cake from the separation membrane, reduces membrane fouling, and facilitates the regeneration of the filtration medium. The physical method improves the dehydration efficiency of waste mud and the recovery of the liquid phase. A string vibration model of the filter screen is established to study the amplitude, acceleration, and stress-strain characteristics under different vibration frequencies. Results show that the amplitude fluctuations of surface particles on the filter screen follow a parabolic trend with frequency variation; amplitude fluctuations near the edges of the screen are greater than at the center, with the most pronounced fluctuations occurring at 40 Hz. Particles near the excitation source exhibit strong periodic oscillations. Acceleration varies significantly with frequency, showing intense fluctuations between 40 Hz and 50 Hz. Surface particle oscillations are periodic, with rapid velocity fluctuations near the excitation source. When the frequency exceeds 40 Hz, acceleration sharply increases, then drastically decreases after 60 Hz. Compared with traditional vibrating screens, the string vibration process produces heterogeneous particle oscillations on the filter surface with higher acceleration magnitudes and faster variation rates, thereby facilitating more effective detachment of materials.