On the Design of a Methodology for Camber Morphing Optimisation with Noise Reduction

31/05/2019

In order to decrease the emitted airframe noise by a two-dimensional high-lift configuration during take-off and landing performances (NLR7301 with trailing edge flap), a morphing airfoil has been designed through a shape design optimisation procedure starting from a baseline airfoil (NLR7301), with the aim of emulating a high-lift configuration in terms of aerodynamic performances. A methodology has been implemented to accomplish such aerodynamic improvements on the aforementioned baseline airfoil by means of the compressible steady RANS equations at a certain angle of attack, with the objective of maximising its lift coefficient up to equivalent values regarding the high-lift configuration, while respecting the imposed structural constraints to guarantee a realistic optimised design. For such purpose, a gradient-based optimisation through the discrete adjoint method has been undertaken. Once the optimised airfoil is achieved, unsteady simulations have been carried out to obtain surface pressure distributions along a certain time-span to latter serve as the input data for the aeroacoustic prediction framework, based on the Farassat 1A formulation, where the subsequent results for both configurations are post-processed to allow for a comparative analysis. Conclusively, the morphing airfoil has proved to be advantageous in terms of aeroacoustics, in which the noise has been reduced with respect to the conventional high-lift configuration for a comparable lift coefficient, although being penalised by a significant drag coefficient increase due to stall conditions on the morphing airfoil's trailing edge.

Autores da comunidade :

• 

  R

  Robert Valldosera Martinez

  ist189022

Orientadores desta instituição:

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  F

  Frederico Afonso

  ist156309

• 

  F

  Fernando José Parracho Lau

  ist13198

mechanical-engineering - Engenharia Mecânica

eng - Inglês

Instituto Superior Técnico