Review of using surrogate models including CFD. methods to determine the appropriate strategy of aerodynamic optimization of the helicopter rotor

A review of the general strategies used in the aerodynamic optimization of the helicopter rotor has been done. The aim is reducing the computational resources of the optimizing process of the new aerodynamic designs of the rotor. This study begins with a brief review of the concepts and sources of the unsteady aerodynamics and the fundamental challenges to addressing this fundamental problem in helicopter rotor design and optimization. Then, past and present design and optimization methods used or proposed and the development of analysis tools to evaluate rotor performance reviewed to gain a better understanding of the problem. The results showed that despite the use of classical aerodynamics, wind tunnel, model rotor experiments and aerodynamic calculations in the past, the recent development of computational fluid dynamics (CFD) now provides an opportunity to accurately predict the viscous and compressible flow field and provide predicting the new rotor designs performances’. Therefore, the use of these tools for highfidelity simulations along with the use of surrogate modeling methods with variable fidelity will cover most aspects of the aerodynamic optimization problem of the helicopter rotor with reduced computational and time resources.