Blade Envelopes Part II: Multiple Objectives and Inverse Design

TL;DR

This paper extends the blade envelope workflow to handle multiple objectives, enabling engineers to optimize manufacturing guidelines considering various performance criteria through inverse design techniques.

Contribution

The paper introduces a multi-objective extension to the blade envelope workflow, incorporating vector-valued models for independent control of flow features and performance metrics.

Findings

Successfully applied to LS89 turbine blade

Controlled loss, mass flow, and Mach number distribution

Produced 3D visualizations of invariant designs

Abstract

Blade envelopes offer a set of data-driven tolerance guidelines for manufactured components based on aerodynamic analysis. In Part I of this two-part paper, a workflow for the formulation of blade envelopes is described and demonstrated. In Part II, this workflow is extended to accommodate multiple objectives. This allows engineers to prescribe manufacturing guidelines that take into account multiple performance criteria. The quality of a manufactured blade can be correlated with features derived from the distribution of primal flow quantities over the surface. We show that these distributions can be accounted for in the blade envelope using vector-valued models derived from discrete surface flow measurements. Our methods result in a set of variables that allows flexible and independent control over multiple flow characteristics and performance metrics, similar in spirit to inverse design methods. The augmentations to the blade envelope workflow presented in this paper are demonstrated on the LS89 turbine blade, focusing on the control of loss, mass flow and the isentropic Mach number distribution. Finally, we demonstrate how blade envelopes can be used to visualize invariant designs by producing a 3D render of the envelope using 3D modelling software.