Generic wrap-around shape optimisation technology is presented, and is applied to a helicopter rotor in hover, using compressible CFD as the aerodynamic model. An efficient domain element shape parameterisation method is used as the surface control and deformation method, and is linked to a radial basis function global interpola- tion, to provide direct transfer of domain element movements into deformations of the design surface and the CFD volume mesh. This method is independent of mesh type and size, and optimisation independence from the flow solver is achieved by obtaining sensitivity information for an advanced parallel gradient-based algorithm by finite-difference. The method has been applied previously to fixed-wing cases, and is applied here to hovering rotors, comparing the effects of global twist parameters and more local parameters. Significant torque reductions are achieved in both cases, and it is shown that using only three global twist parameters are extremely effective. Using 63 local and global parameters, large geometric changes are demonstrated, with both induced power and wave drag reduced.
|Translated title of the contribution||Aerodynamic shape optimization of hovering rotors using compressible CFD|
|Title of host publication||Royal Aeronautical Society Aerodynamics Conference, Bristol, UK|
|Number of pages||9|
|Publication status||Published - Jul 2010|