Unsteady flow field analysis of suction surface adjustable vane

The variable area guide vane is a core component of variable cycle engine. At present, the main type of variable area vane works by varying the installation angle. However, leakage flow and varied installation angle introduce pressure losses and offset the gains of the variable cycle. This paper investigated the suction surface adjustable guide vane as an alternative type to the variable installation angle guide vane. The delayed detached-eddy simulation method was adopted to analyze the pressure waves, shock waves, wake vortices, and the interference between shock waves and wake vortices for the suction surface adjustable guide vane. The mass flow rate, pressure loss characteristics, and outlet flow angle of suction surface adjustable guide vane and variable installation angle guide vane were compared. The results indicated that in the suction surface adjustable guide vane, when the suction surface rotated by 5°, two shock waves appeared, and the shock waves accelerated the dissipation speed of wake vortices. For suction surface adjustable guide vane, when the mass flow rate decreased by 17%, total pressure loss coefficient increased by 0.04, and the outflow angle decreased by 2.2°. For variable installation angle guide vane, under the same mass flow adjustment, the total pressure loss coefficient increased by 0.06–0.09, and the outlet flow angle changed by 5°–7°. The suction surface adjustable guide vane demonstrated effective control of flow capacity, with lower pressure losses and smaller changes in outlet flow angle compared with the variable installation angle guide vane.