Study of the Injection of Secondary Air into the Intake Manifold of the Gas Turbine to Avoid the Compressor Surging Phenomenon

This paper presents part of the research on avoiding or reducing the surging effects that appear in the axial compressor intake manifold of a gas turbine. This research has led to an original solution validated by numerical simulations and experimental investigations. The increased amount of air suddenly required in the transient regime of the gas turbine is introduced into the intake manifold through slits arranged perpendicular to the direction of flow, on an aerodynamic profile at a certain angle to it and a certain distance from the minimum transversal section. The slits are arranged on the opposite sides of the gallery and connect with a transverse channel of the airfoil, in which there is air under pressure, from which the introduction of additional air is ordered. The numerical and experimental results extended to the influence of many geometric and mechanical parameters, proving that the proposed solution is as effective as possible compared to the classic ejector solution.