A Novel Design towards Reducing Leakage Loss for Variable Geometry Turbines

To accommodate the next generation of adaptive/variable cycle engines and gas turbine power, variable geometry (VTG) is widely acknowledged as a most essential component. VGT consists an adjustable vane to address combined goals high dry thrust low specific fuel consumption (SFC) at subsonic cruises for aero-engines. This concept allows engine operate constant bypass ratio over wide range pressure ratios. avoid scraping during rotation guide vanes, typical gap deliberately left, which leads significant leakage loss. In this research work, novel spherical convex plat with pivot shaft proposed, can be obtained by additive manufacturing. The sophisticatedly designed according aggressive tip/hub gradient. design naturally generates blockage from side towards suction side. As result, gradient removed, maximum flow eliminated. overall loss reduced. simple rotating structure improve efficiency 0.4–3.0% within considered. Based on understanding mechanism, radially restacked another extra 0.2% improvement achieved. universal philosophy also verified different loading blade profiles, i.e., front-, middle- aft-loaded vane. improved aerodynamic performance achieved idea.