Traverse Measuring Device Used For The Wind Tunnel Flow Field Measurement

Wind tunnel is the key test equipment for aerodymanic research.After the completion of the wind tunnel,in order to check whether the installation of the wind tunnel segment parts meet the design requirements,and whether the flow field fullfils the national standard,it is necessary to carry out a series of flow field calibrations.Measurement of the flow field orimentation is the most difficult part among all the flow field calibrations.Comb-tube measurement device is commonly used in orientation field measurement,whose test resul ts are seriously affected by the deflecton of 5-hole probe.In order to reduce the interference derived from the deflection of 5-hole probe,a single-point traverse measurement device is developped in this paper to be used in recently built 4m wind tunnel.The traverse measurement structure is specially designed to ensure its feasibility and rationality.The stiffness and strength of critical parts are calculated in order to guarantee its safety under high speed wind velocity.The flow field test is remotely controlled and the data is automatically collected during one comission.The efficiency and accuracy can be improved remarkably.As the core device in flow field calibration,the machining accuracy of the 5-hole probe determines the accuracy of test results.The 5-hole probe is installed on the traverse measurement structure,and get the velocity and orientation of each point.The flow field distribution could be obtained through the movement of the probe to different points inside the wind tunnel.The initial machining coefficient of 5-hole probe is obtained through wind tunnel tests,in order to ensure it is acceptation in 4m wind tunnel.The orientation field curves is drafted through test results.It is indicated from the curves that the orientation results of the flow are below 0.5°.So the traverse measurement device is rational and can be used as a new structure in flow orientation test.