Study on the Flow Characteristics of Non- Newtonian Drilling Fluid Through Vibrating Screen Meshes

Composite screens are a critical component of drilling fluid shale shakers, and their performance directly affects the recovery efficiency of drilling fluid. This study focuses on the composite screens of shale shakers and simulates the flow of non- Newtonian drilling fluids through different structures of composite screens to investigate the impact of drilling fluid rheological parameters and screen compo-sitions on screening performance. The research results indicate that the flow velocity of the drilling fluid is the highest while passing through the lower screen, and the turbulent kinetic energy (TKE) is at its maximum in the lower screen area, where energy dissipation is also the greatest. An increase in the rheological parameters of the four- parameter model drilling fluid generally increases the difficulty of passing through the screen, with the flow behavior index and viscosity coefficient having a particularly significant impact on the pressure drop coefficient. Compared with the plain composite screen, the herringbone composite screen and plain patterned composite screen have lower pressure drop coefficients, with the herringbone composite screen demonstrating the best screening performance. These findings provide theoretical references for flow analysis and structural optimization of shale shaker screens in drilling fluid applications.