Airfoil Optimization using Design-by-Morphing

TL;DR

This paper introduces Design-by-Morphing (DbM), a new methodology for creating flexible search spaces for 2D airfoil shape optimization that enables radical design exploration and improves aerodynamic performance.

Contribution

The paper presents DbM, a novel shape design methodology that avoids geometric constraints, allowing for extensive exploration and optimization of airfoil shapes with few parameters.

Findings

Created a Pareto front of airfoils with high lift-over-drag ratios

Achieved radical and large shape variations in the search space

Optimized airfoils with remarkable aerodynamic properties

Abstract

We present Design-by-Morphing (DbM), a novel design methodology applicable to creating a search space for topology optimization of 2D airfoils. Most design techniques impose geometric constraints and sometimes designers' bias on the design space itself, thus restricting the novelty of the designs created, and only allowing for small local changes. We show that DbM methodology does not impose any such restrictions on the design space and allows for extrapolation from the search space, thus granting truly radical and large search space with a few design parameters. In comparison to other shape design methodologies, we apply DbM to create a search space for 2D airfoils. We optimize this airfoil shape design space for maximizing the lift-over-drag ratio, $CLD_{max}$, and stall angle tolerance, $\Delta \alpha$. Using a bi-objective genetic algorithm to optimize the DbM space, it is found that we create a Pareto-front of radical airfoils exhibiting remarkable properties for both objectives.