Comparative analysis of guide vane edge profiles in LPBF-manufactured elbows for enhanced flow performance

As a widely used pipeline structure in hydraulic systems, elbows suffer significant energy loss due to internal vortices. Laser Powder Bed Fusion (LPBF) offers a novel technical approach for designing and manufacturing hydraulic elbows. However, internal channel structures often feature large-angle overhanging surfaces, which are susceptible to internal and surface defects caused by unstable molten pool flow during the forming process. In this paper, guide vanes are introduced to provide internal structural support for the elbow. To mitigate pressure concentration and vortex shedding, a parametric comparative analysis was conducted on guide vanes with specific edge profiles, proposing two novel configurations: the Smooth-Sharp and the Double-Sharp guide vane. Through numerical simulation and experiments, the effects of vane shape and structural parameters on flow field structure, pressure loss, and Turbulent Kinetic Energy (TKE) were investigated. Results show that the Double-Sharp guide vane performs best, effectively disrupting large-scale secondary flows and vortices while suppressing flow separation. In a 10 mm diameter hydraulic elbow, a 0.25 mm thick Double-Sharp vane reduced local resistance by over 9.95%, attenuated peak pressure drop by 47.29%, and significantly lowered peak turbulent kinetic energy. This work provides a new theoretical basis for the integrated design of high-performance additively manufactured hydraulic pipelines.