Resumo:
Inverse methodologies continue to be important computational tools for the design of
flow machines, despite the sophisticated methods currently available for the analysis of viscous
three-dimensional flows. A Quasi-Three-Dimensional methodology based on the
interdependent solution of two inverse problems is described in this work: the through-flow
problem and the blade-to-blade problem. The developments continue the research by Santos et
al. (2012) and Barbosa (2018). The solution to the through-flow problem – referring to the work
of Santos et al. (2012) - provides the shape of the mean flow surface and the results of the
streamlines, to meet a given hydraulic momentum distribution. The inverse blade-to-blade
problem – referring to the developments of Barbosa (2018) – provides the geometry of the
blades, given a finite number of blades, on surfaces of revolution whose generatrices are the
streamlines resulting from the through-flow problem. Until then, the effects of thickness and
blocking were disregarded. In this work, a methodology for including thickness distributions
along the blades is described. The thickness effect is analyzed through the direct solution of the
blade-to-blade problem (now considering profiles) using the panel method based on linear
vortex distributions. The corresponding blocking factors are calculated, and the results feed the
input of a new solution of the through-flow problem. Thus, the through-flow problem and blade to-blade become coupled. The geometry is recalculated, now considering the effect of thickness
and blocking. Furthermore, the effects of a) hydraulic momentum distribution; b) finite number
of blades; c) thickness; d) blocking; e) combination of b), c) and d); and f) profile stacking line
on the geometry of the blades and their hydrodynamic loads are analyzed.
