| The airfoil flutter is a dangerous self-excited vibration which will destroy the aircraft structure in a few seconds and then result in flying accidents once it does happen. In recent years, the high-altitude long-endurance uninhabited air vehicles(UAV) have been widely used in many countries due to their unique advantages in the long-term surveillance and monitoring. The flutter problems of this type of UAV are more significant due to their high-aspect-ratio wings.There are two main ways to carry out the research on the flutter of the high-aspect-ratio wings: numerical calculation and experiment means. The former has a certain reference value, but may have a large deviation with the actual situation. The latter includes wind tunnel test and flight test, while both of them have high cost and risk. In allusion to the above problems, the main contents of this paper are as follows:Firstly, the object of study and the basic concept of flutter are introduced in detail. Secondly, the method of ground flutter simulation and monitoring is proposed, of which the concrete way to realize the ground flutter simulation is by external vibration exciter and closed loop control system, and meanwhile the flutter state is monitored by identifying the current modal parameters on line. In addition, the strain of the main beam is also monitored in real time in order to prevent the wing from being damaged. Subsequently, the system of flutter and condition monitoring of high-aspect-ratio wing is designed based on the above method. Finally, the experiments are carried out, and the results show that the system has successfully simulated the divergent state and limit cycles state of wing flutter, meanwhile it has also realized the condition monitoring function. |
