摘要
北京大学低速风洞新研制的大攻角强迫振动实验设备可迫使模型绕其体轴做单自由度俯仰、偏航、或滚转振动,由六分量应变天平感受气动反作用力和力矩,测量仪器按相关滤波原理将它们分解为同相分量和正交分量。仪器具有很高的分辨度和精度,能测出组合形式的全部18个同相导数和18个正交导数。该设备具有很大的攻角范围和侧滑角范围,并具有足够大的振动频率和振幅范围,实验风速可从20米/秒至50米/秒。强迫振动风洞实验的全过程都在微机控制下自动、实时地完成。通过某教练机的强迫振动实验和不同方法的对比实验表明,该设备能较好地测量出组合形式的全部阻尼导数、交叉导数和交叉耦合导数。
In this paper,rigs and techniques for forced oscillation at high angle of attack in a low-speed wind tunnel,is presented.The modelcan be tested in pitching,yawing,or rolling oscillation about its bodyaxis system.All the combined damping derivatives,cross derivatives andcrosscouplingderivatives can be obtained by six-component strain balanceand dynamic data acquisition system.
关键词
强迫振动
多分量天平
大攻角
风洞
forced oscillation
multi-components
balance
high angle
dynamic stability derivatives
test techniques