Evaluation of Surrogate-Based Modeling Methods for the Optimization of Helicopter Rotor Structures for Minimum Vibration

2019-11-02
Helicopters are notorious for their high vibration levels and the rotors are the main contributors. At preliminary stages, it is essential to design the rotors to achieve minimum vibration amplitudes, which is generally realized by using optimization routines. The optimization of a helicopter rotor for minimum vibrations requires repeated high-fidelity solutions, which lead to high computational times. Moreover, since the rotor optimization problem contains many local minima by its nature, the optimization process might be repeated in order to guarantee the global minimum, which results in increased solution times. In this study, surrogate-based models for the prediction of optimization results are investigated to reduce the computational expense for the optimization of a four-blade rotor. The composite rotor blade cross-sectional design parameters are utilized for the optimization and the rotor is assumed to be in a high-speed forward flight. Along with vibration minimization, the minimum blade mass is also targeted and both of the objectives are subjected to a number of static and dynamic constraints. The objectives and the constraints are written as functions of design variables and for each function, a surrogate model is constructed. To reduce prediction errors in the surrogate model, data transformation techniques are employed. Using these surrogate models, the rotor is optimized. It is concluded that by using surrogate-based modeling and data transformation techniques, computational time required by the optimization process can be significantly reduced without compromising the optimization accuracy.
8th Asian/Australian Rotorcraft Forum, 31 Ekim - 02 Kasım 2019

Suggestions

Development of a hybrid global optimization algorithm and its application to helicopter rotor structural optimization
Bilen, Muhammed Emre; Özgüven, Hasan Nevzat; Department of Mechanical Engineering (2019)
Helicopters are notorious for their high vibration levels and the rotor system are the main contributors to the problem. The rotor vibrations can be minimized by optimizing the rotor structure, which require time-consuming high-fidelity solution for vibration predictions. To solve this problem, an effective and efficient global search algorithm called Explorer-Settler Optimization algorithm is developed by combining the advantageous aspects of Particle Swarm Optimization and Nelder-Mead Optimization algorit...
Integration of Parameter Sensitivity to Structural Optimization of Helicopter Rotors for Minimum Vibration
Bilen, Muhammed Emre; Ciğeroğlu, Ender; Özgüven, Hasan Nevzat (CRC, New York , 2020-10-01)
Helicopters are notorious for their high vibration levels and the rotor systems are the main contributors to the problem. Rotor vibrations can be minimized by optimizing the rotor structure. However, the result of the optimization might require precise manufacturing of the rotor with tight tolerances leading to increased production cost and time. Moreover, due to loose manufacturing tolerances or wear from usage, the rotor might present higher vibrations during operation if the rotor vibration is sensitive ...
Integration of parameter sensitivity to structural optimization of helicopter rotors for minimum vibration
Bilen, Muhammed Emre; Ciğeroğlu, Ender; Özgüven, Hasan Nevzat (CRC, New York , 2020-10-01)
Helicopters are notorious for their high vibration levels and the rotor systems are the main contributors to the problem. Rotor vibrations can be minimized by optimizing the rotor structure. However, the result of the optimization might require precise manufacturing of the rotor with tight tolerances leading to increased production cost and time. Moreover, due to loose manufacturing tolerances or wear from usage, the rotor might present higher vibrations during operation if the rotor vibration is sensitive ...
Estimation of Critical Submergence at Single Horizontal Intakes Under Asymmetric Flow Conditions
Haspolat, Emre (2022-01-01)
Air-entraining vortices are one of the serious hydraulic phenomena which can create various problems during the operation of intakes. Generally, air-entraining vortices start to form when the intake submergence is insufficient and less than a critical value. The purpose of the present study is to investigate the formation of air-entraining vortices and determine the critical submergences at single horizontal intake under asymmetrical approach flow conditions by conducting experiments with four different pip...
Acoustic Fatigue and Dynamic Behavior of Composite Panels Under Acoustic Excitation
Uz, Canan; Ata, Tamer T. (2016-01-28)
Composite panels in aircraft structures are exposed to fluctuating sound pressure originating mostly from engine noise and air flow. In this paper, acoustic fatigue and dynamic response of composite panels under acoustic excitation are investigated numerically. Composite panel is simulated with finite element analysis. The panel is considered clamped at one edge, whereas the opposite edge is assumed to be free. The panel is subjected to random repeated loading generated by sound waves. The analysis estimate...
Citation Formats
M. E. Bilen, E. Ciğeroğlu, and H. N. Özgüven, “Evaluation of Surrogate-Based Modeling Methods for the Optimization of Helicopter Rotor Structures for Minimum Vibration,” presented at the 8th Asian/Australian Rotorcraft Forum, 31 Ekim - 02 Kasım 2019, Ankara, Türkiye, 2019, Accessed: 00, 2021. [Online]. Available: http://www.arf2019.org/.