Enhanced Blade Row Matching Capabilities via 3D Multistage Inverse Design and Pressure Loading Manager

Abstract

Three-dimensional inverse design has become a reliable and powerful tool for facilitating the refinement of blading designs. Its main strength lies in the direct control offered over local aerodynamics and, when the method is based on pressure loading, net circulation. While the ability to specify pressure loading offers many advantages, it is often not obvious to a designer what loading distribution should be prescribed. Not only should a suitable blade shape be achieved, but also satisfactory performance and design constraints such as mass flow, exit flow angle distributions and compression ratio. This problem is exacerbated when applying inverse design in a multistage environment, where interactions between blade rows affect the design and the resulting flow field in ways that are often intractable. Thus, numerous revisions of the prescribed loading, with a careful examination of how changes to the prescribed loading influence the resulting design, can still be necessary before obtaining a satisfactory design. A pressure loading manager has been developed to alleviate these problems. This loading manager can automatically adjust pressure loading distributions during the inverse design process to achieve greater control over the aerodynamic design intent. In combination with a fully three-dimensional multistage viscous inverse design method, a powerful method for blading revision is obtained that offers enhanced aerodynamic matching capabilities and design point control. Increased aero-design quality and productivity in difficult design situations can be achieved. This is demonstrated with the redesign of a highly loaded 2.5-stage transonic compressor.