Optimizing the Aerodynamic Efficiency of an Aircraft Nacelle

Optimal Solutions Sculptor™ coupled with a multi-objective optimization code produced a design that showed a decrease in drag of more than one percent, a significant amount when the duty cycle of a typical nacelle is considered; this was done while decreasing the mass flow by less than 0.02 percent, increasing the overall efficiency of the nacelle. Moreover, Sculptor avoided time consuming operations on the Computer Aided Design (CAD) model and on the computational grid, since its morphing takes place over the model directly.

A simple optimization was setup for this nacelle. The goal was to reduce drag, while maintaining flow through the nacelle. Three parameters were setup to accomplish this task. The first parameter would change the radius of the inlet, the second would rotate the inlet of the nacelle and the third would translate the inlet in the x direction. Sculptor’s morphing technology was applied over a Computational Fluid Dynamic (CFD) model of the nacelle, to define the optimal surface for drag. The original mesh was read into Sculptor, and the model was prepared for morphing.

Using Arbitrary Shape Deformation (ASD) volumes over 35 different configurations were instantly tested, without the need of re-creating the mesh. By moving the control points, new configurations were created immediately and then submitted to CFD. Finally, the configuration giving the best results was chosen.