Flow Induced Vibration And Aerodynamic Interference Research About The Application Of Wire-driven Parallel Robot In Wind Tunnel

The Wire-Driven Parallel robot with 8 wires in a low-speed wind tunnel,because of the advantages such as little interference to the flow field around the model plane and high efficiency of completing various complex motion,provides an effective way of model supporting for the wind tunnel test.Using the ANSYS software,this paper gives the detail analysis of flow induced vibration characteristics of the wires affected by flow field when the Wire-Driven Parallel robot isapplied in a low speed wind tunnel test.First of all,the pre-tension of the wires in the Wire-Driven Parallel robot is simulated and the best pre-tension that meets the demand of basic work condition under low airspeed is determined.Secondly,the influence of different positions of the wires in the flow field to the wires’ vibration characteristics is analysed.It is found that the change of wire positions has less effect on wire vibration characteristics butmore on the maximum vibration amplitude,the direction of which will not change.In order to expand the application scope of the Wire-Driven Parallel robot under different airspeeds,this paper analyzesvibration characteristics of the wire under different flow velocity.Finally,the influence of the flow-induced vibration to the barycenter of the aircraft model is analyzed.In addition,to explore thefeasibility of the application of wire-driven parallel support technology in hypersonic wind tunnel.This paper gives details of an investigation of the aerodynamic interference and the stiffness issue referring to the application of wire-driven parallel robot with 8 wires(WDPR-8)in hypersonic wind tunnel.The parallel suspension system with 8 wires were constructed and the 10°cone model is selected as the test model,the position and pose of which can be adjusted through the wire length.Under the condition of Ma=7.8,the aerodynamic coefficient of the model suspended with WDPR at different angle of attack is calculated in CFD.The comparison between simulation result and the result of the same model without wires and the reference data indicates that,at small angle of attack,the relative error of the aerodynamic interference caused by the wires is small,and the interference increases with the angle of attack.In particular,the axial force coefficients need to be modified to improve data accuracy.In addition,modal characteristics of the wire-driven parallel robot and the crescent shape support system are analyzed and natural frequencies of the two support systems are compared.The comparison result shows that the natural frequency and the stiffness of the WDPR-8 are higher than that of the crescent shape support system.The research work of this paper provides reference to the application of wire-driven parallel support technology in hypersonic wind tunnel.