Development Of Airfoil Pressure Measuring System For Low-speed Wind Tunnel Test

The airfoil pressure measurement test as one of the most important aerodynamics experiments is commonly used in teaching and research.The emphasis on the airfoil pressure measurement test is that a data acquisition system should be developed to meet the need of the test.With the development of virtual instrument,it is possible to develop a kind of airfoil pressure measuring system based on hardware related and virtual instrument.Starting from the aspects such as basic principle,requirement analysys, experimental process,handware procurement and software platform,the task of the measuring system based on the software such as Labview is finished.First,Starting from the principle of aerodynamics and data acquisition,the knowledge of the system development is introduced.What's more,the kind and size of airfoil is chosen. Second,according the natural process of the airfoil experiment,the pressure data of surface are acquired to guide the real experiment by two-dimensional numerical simulation. Third,the optimization problem of holes basd on the method of B-spline curve fitting using firefly algorithm in pressure measurement is also studied in this paper. Compared with other intelligent algorithms, the adaptability of firefly algorithm significantly is higher than other intelligent algorithm. In condition of less holes(n = 4),firefly algorithm can still converge in 10 iterations, but other intelligent algorithms can not do that. The accuracy of firefly algorithm is 20% higher than that of traditional methods in condition of the same number of holes,.What's more,the problem of population initialization in high-dimensional simplex is solved. Fourth, the material of model is confirmed by calculation. The kinds of pressure transmitter and acquisition card is also chosen. At last,the platform of the system is made by Labview,including the parts such as operation,acquisition and storage.Finally,a data acquisition system used in airfoil pressure measurement test is born by the research. The system not only meet the needs of small and middle-sized wind tunnel, but also has practicability and the value which can be promoted.