Numerical Investigation of Influence of Tangent Pitch and Slanting Flow of Guide Vanes on the Axial Compressor Stage Parameters

• Main Authors: D. V. Arkhipov, R. Z. Tumashev
• Format: Article
• Language: Russian
• Published: MGTU im. N.È. Baumana 2015-01-01
• Series: Nauka i Obrazovanie
• Subjects: axial compressor; stage; guide vane; numerical simulation; gas-dynamic stability margin; efficiency; tangent pitch; slanting flow
• Online Access: http://technomag.edu.ru/jour/article/view/113

<p>The flow redistribution in the axial stage through the stator axis blade deformation can create favorable conditions for raising stage efficiency and combined actions for axial compressor elements especially in ambient conditions. For this purpose, the axis deformation impact on the gas-dynamic stability margin and the coefficient of efficiency of axial compressor has been numerically investigated.</p><p>The influence of guide vane (GV) axis was considered with invariable rotor blades and different variants of stator. The GV axis form was changed on the arc of a circle in the range of ± 15% guide vane height in circumferential direction and in the axial direction in the range ± 10% of guide vane height, increments ± 2.5%.</p><p>As an object, for investigation was chosen a numerical 3D model of transonic stage of axial compressor with the following values of basic parameters: circumferential speed in the rotor blade trips of 345 m/s, relative diameter of the hub being 0.7, and coefficient of discharge being 0.5. The stage was profiling by classic low Cu*r=const. Rotor and stator profiles for all variants under investigation were the same in the same radii.</p><p>As to initial radial axis guide vane, the losses of total pressure in stator become substantially less throughout the height of blade in case there is a guide vane axis bending in axial direction in line of flow. Bending of the axis in the circumferential direction against the rotation leads to reducing total pressure losses especially in hub and shroud regions, and in the flow core there is no change.</p><p>In future, the effects of a tangent pitch and a slanting flow can be of interest in case of the simultaneous bending in both directions, as well as when studying the influence of bending of the guide vanes, which are a part of a sector of stages and a multi-stage compressor in a wide range of operating conditions.</p>