Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
INFLUENCE OF RADIAL DISTRIBUTION OF ANGULAR MOMENTUM ON GEOMETRY OF ROTOR BLADES OF A MINI HYDRAULIC BULB-TURBINE
Submission Author:
Luís Morão Cabral Ferro , RN
Co-Authors:
Luís Morão Cabral Ferro
Presenter: Luís Morão Cabral Ferro
doi://10.26678/ABCM.COBEM2019.COB2019-1455
Abstract
INFLUENCE OF RADIAL DISTRIBUTION OF ANGULAR MOMENTUM ON GEOMETRY OF ROTOR BLADES OF A MINI HYDRAULIC BULB-TURBINE Luís Morão Cabral Ferro Luiz Carlos do Norte Oliveira Department of Engineering and Technology, Universidade Federal Rural do Semi-Árido, Brazil lferro@ufersa.edu.br, lcno1@msn.com Abstract. The geometry of the rotor blades of an axial turbine are usually designed from the specification of velocity diagrams on the inlet and outlet sections of the rotor. The author has used a methodology with a constant radial, spanwise, distribution of angular momentum at inlet and outlet sections, with a prescribed non-zero value at inlet section of the rotor and zero at the outlet. The three-dimensional viscous flow through the rotor is replaced by the quasi-three-dimensional approach. The flow on radial and axial surface, S2 surface as described is replaced by an axisymmetric flow, and the flow on circumferential and axial surface, S1 surface, is approximated by a two-dimensional flow through a linear cascade of profiles. In this paper the influence of the angular momentum distribution along the spanwise at inlet section is analysed. The axisymmetric flow is computed using a streamline curvature method. Nine different laws of radial distribution of angular momentum, (constant, linear, quadratic, quadratic positive and negative, inverse, quadratic inverse, quadratic inverse modified and modified inverse) are compared. Spanwise profiles of velocity components as well as velocity angles, pressure and velocity coefficients at inlet at outlet sections of guide vanes and rotor are presented. Keywords: rotor, axial-flow turbine, angular momentum, streamline curvature method, panel method.
Keywords
rotor, axial turbine, Angular Momentum, streamline curvature method, panel method
