Вплив інжекції повітря у вхідні стійки турбовального двигуна

Abstract

The aerodynamic wakes behind the struts cause uneven flow at the compressor inlet. An irregularity at the compressor inlet of a turboshaft engine causes unstable operation of the compressor, which can deteriorate the engine economy and a decrease its efficiency. The current work evaluates the effect of injection of an additional mass of air into the inlet struts of a TV3-117 turboshaft engine on the velocity non-uniformity at the compressor inlet. The solution of the task was carried out by the method of mathematical modeling using the free version of the Ansys Workbench Student software environment. When solving the problem, several modules were involved: Geometry (creation of geometry), Mesh (generation of the computational mesh), CFX (selection of boundary and initial conditions, calculation and visualization of the calculation). The blade rim of the input racks of a TV3-117 turboshaft engine was chosen as the object of study in this work. Analysis of the results obtained shows that by using the injection of additional air mass, it is possible to reduce the unevenness of the speed at the compressor inlet. When injected with a mass flow rate of 2.2...2.8% of the main mass flow rate at inlet speeds of 100...160 m/s, the speed unevenness at the compressor inlet decreases from 10...12% to 3...4%. Thus, the velocity field in front of the compressor will be nearly uniform, which will positively affect its performance. An analysis of the visualizations of the velocity fields shows that when additional air mass is injected, the aerodynamic wake changes qualitatively and decreases significantly, the speed in the wake at a distance of 10 mm differs from the speed in the flow core by 3%, in contrast to the case without boundary layer control, where the speed in the wake it differs in speed in the core of the flow by 10...12%. To control the boundary layer in the blades of the input racks, it will not be necessary to supply additional air because air that is already supplied to heat the input racks can be used for this. The design of the inlet leg blade with control of the near-boundary layer will be quite complicated, but it is possible to implement the developed inlet leg blade design for controlling the boundary layer in the trailing edge using modern 3D printers.