The curved rod of carbon fibrecomposite is the key component of the large angle three degree of freedom virtual flight test device. This article takes the composite curved rod as the research object, Establish a finite element analysis model and analyze its strength and stiffness under the initial design conditions, the RSM response surface approximation model and multi-island genetic algorithm are used to optimize the carbon fibre composite angle of each layer of the composite curved rod, so that the maximum deformation displacement of the curved rod is minimized, As far as possible, the influence of the center of mass of the Virtual flight test model on the wind tunnel test data should be reduced. The optimization results show that relative to the initial design, the failure factor of the composite curved rod is reduced by 65.4%, the rigidity is increased by 35.94%, and the maximum deformation is reduced by 44.5%. In order to realize the simulation of flight motions close to 90 ° angle of attack in a horizontal wind tunnel, it provides equipment guarantee for the research of stall deviation, initial phase of spin and stable spin.

The helicopter rotor wing wind tunnel test model is the basic equipment for helicopter wind tunnel test research. On the premise of meeting the requirements of corresponding strength, stiffness, natural frequency and stability, the model mass needs to be light enough to meet the requirements of heave vibration test. To this end, this paper proposes the structure of aluminum alloy skeleton + carbon fiber reinforced composite skin, and in order to obtain good performance, the following steps are used to optimize the parameters of the test model structure: 1. Establish an RBF neural network approximation model; 2. Use multiple island genetic algorithm (MIGA) and the sequential quadratic programming algorithm (SQP) are combined to optimize the thickness of the skeleton and composite materials. The optimization results show that the quality of the model is reduced by 34.05% under the condition that the corresponding requirements of strength, stiffness, natural frequency and stability are met.

A novel split parallel multicomponent strain sensor structure layout is proposed based on the special requirements of the helicopter rotor airfoil wind tunnel test for measuring aerodynamic sensors. The sensor consists of two splits with the same configuration; the performance of the sensor not only depends on the split structure of the sensor but also depends on the assembly relationship between the splits. Three steps have been performed so as to enhance the technical performance of the sensor. First, the RBF neural network approximate model and the second-generation nondominated sorting genetic algorithm are used to optimize the split of sensor deterministically; secondly, the rotor airfoil wind tunnel test model and the sensor finite element system model are established, and the 6 σ robustness analysis is carried out; finally, the 6 σ robust multiobjective optimization has been carried out considering the sensor split processing errors and the assembly errors. The results show that, compared to initial designed sensors, the sensitivity of the three components of the sensor is increased by 285.46%, 284.95%, and 151.5%, respectively, and the maximum equivalent stress is reduced by 28.4%; the interference to the three components is reduced by 97.82%, 92.83%, and 99.8%, respectively, and the quality is reduced by 25.74%. Meanwhile, the quality level of the sensor was promoted, and the sensitivity of the response to assembly and manufacturing errors were reduced. These results exhibit that the structural layout, optimized path, and method in this strain sensor are suitable for the needs of helicopter rotor airfoil wind tunnel test.

The low-frequency pressure pulsations in a large low-speed open jet wind tunnel were studied using a 1:20 scaled model wind tunnel. It was found that plane pressure standing waves existed in all three directions of the wind tunnel’s plenum. It was confirmed that the large pressure pulsations in the transverse direction of the plenum were caused by the resonance of the plane pressure standing waves in that direction with the edgetone feedback (vortex-sound feedback between the nozzle and the collector). The analysis of the standing waves in the vertical direction of the plenum suggested that they might come from self-excited oscillations. For the model wind tunnel with a 1:20 strictly scaled collector, the standing waves in the transverse direction of the plenum were much stronger than those in the other two directions. By increasing the width of the collector, the intensity of the standing waves in the transverse direction was significantly reduced to a level similar to that of the standing waves in the vertical direction. It was also found that the standing waves in the transverse direction were significantly enhanced after a floor was added to the test section.