一种新颖的侧滑振动导数实验技术

北京大学低速风洞中采用一种新的测量侧滑振动导数的原理和技术，它利用同一强迫振动装置，更换少许运动转换件和支杆，实现五种单自由度强迫振动，由六分量天平和相关滤波仪器测量出全部组合导数和下洗时差导数，而侧滑振动导数是通过对应的侧滑－滚转振动与演转振动测出的组合导数之差得到的。本文给出了某教练机大攻角侧洗时差导数的典型结果。

A NEW TESTING TECHNIQUE FOR OSCILLATORY DERIVATIVES OF THE SIDESLIP

In this paper, a new principle and technique for measurements of the sideslip oscillation derivatives are presented. It is a part of the testing techniques for dynamic stability derivatives at high angle of attack, and these techniques have been developed in Beijing University Low Speed Wind Tunnel. Using the same forced oscillation rig and exchanging a few components, five single freedom oscillations can be realized.By means of six -component balance and correlation filter, all the combined derivatives and downwash time-difference derivatives are obtained,and sideslip oscillation derivatives are the difference of the results forthe sideslip-rolling oscillation and the rolling oscillation. In this paper,some typical results of sideslip rate derivatives at high angle of attackfor a trainer arc also given.