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 The general situation was narrated briefly for the development of the threesurface aircraft configurations in general aviation. From the comparison of the theoretical and experimental studies, the present situation is summed up as the conventional, the canard,and the threesurface configurations. On the basis of PM theory, the calculations are made for the induced drag factor, the ratio of lift to drag, and the ratio of lift in surfaces on five kinds of threesurface planes and test models. By means... The general situation was narrated briefly for the development of the threesurface aircraft configurations in general aviation. From the comparison of the theoretical and experimental studies, the present situation is summed up as the conventional, the canard,and the threesurface configurations. On the basis of PM theory, the calculations are made for the induced drag factor, the ratio of lift to drag, and the ratio of lift in surfaces on five kinds of threesurface planes and test models. By means of computation and analysis, distinct difference is found in aerodynamic characteristics for first kind and second kind threesurface configurations: the first kind found to be bigger front surface with shorter distance to wing; the second kind, smaller front surface with longer distance to wing. The influence of level distance from front surface to wing on the induced drag factor and the ratio of lift to drag is fairly large.  本文对国外通用航空中三翼面布局飞机的研究概况作了简要叙述，并归纳了正常式、鸭式和三翼面布局相互对比的理论研究和实验研究状况。根据Ｐ－Ｍ理论，计算了五种三翼面飞机和试验模型的诱导阻力因子、升阻比以及翼面升力比等。通过计算分析，发现大前翼小间距的第一类三翼面布局和小前翼大间距的第二类三翼面布局的气动特性有明显的差别，且前翼与机翼间的水平间距对诱导阻力因子和升阻比的影响较大。  An experimental investigation has been conducted in a 1m wind tunnel to the local flow field around the tip of a rectangular half span wing.This paper gives ayailable results for design of wing tip devices and analyzes the principle of increasing lift and reducing drag for sails.Wind tunnel tests show three sails designed by combined the numerical calculation with results presented in this paper can reduce the induced drag factor by 21. 49 percent.Sails designed in this paper are successful and can be... An experimental investigation has been conducted in a 1m wind tunnel to the local flow field around the tip of a rectangular half span wing.This paper gives ayailable results for design of wing tip devices and analyzes the principle of increasing lift and reducing drag for sails.Wind tunnel tests show three sails designed by combined the numerical calculation with results presented in this paper can reduce the induced drag factor by 21. 49 percent.Sails designed in this paper are successful and can be used for reference to sails design.  在１米低速风洞中，对半展长直机翼翼尖用围空间流场进行了详细地研究，并分析了翼尖帆片的增升减阻机理。根据理论计算并结合试验结果设计的翼尖机片，经大低速风洞全机模型试验证明：翼尖装三个机片可使全机诱导阻力因子减小２１．４９％。这可供帆片设计时参考。  This paper only choose two sets of polar curve measured in flight at h =5 000 m, Ma =0 8,full afterburner condition by J7 aircraft using double pulse horizontal tail,various contradictions and questions occured at C x=f(C y),C y=f(α) were analyzed and explained,and the solution was provided.That is giving C ωz y=f(C y)(Ma=c) by using dynamic flight test data, and using them in balance condition revision of C y for dynamic polar curve.The C y measured in flight is revised to ... This paper only choose two sets of polar curve measured in flight at h =5 000 m, Ma =0 8,full afterburner condition by J7 aircraft using double pulse horizontal tail,various contradictions and questions occured at C x=f(C y),C y=f(α) were analyzed and explained,and the solution was provided.That is giving C ωz y=f(C y)(Ma=c) by using dynamic flight test data, and using them in balance condition revision of C y for dynamic polar curve.The C y measured in flight is revised to C y in balance condition for positive ω z ,resulting induced drag factor value A is increasing rather than reducing.  选用Ｊ７飞机，在ｈ＝５０００ｍ，Ｍａ＝０．８，全加力飞行状态，使用倍脉冲平尾进行飞行试验所测得的两组试验数据及极曲线，对其Ｃｘ＝ｆ（Ｃｙ），Ｃｙ＝ｆ（α）中出现的不合理现象和疑点进行了分析和解释，并提出了解决办法。该解决问题的办法就是用动态飞行试验数据求出Ｃωｚｙ＝ｆ（Ｃｙ），（Ｍａ＝ｃ），并将此数据用于动态极曲线Ｃｙ平衡状态的修正。结果表明，用倍脉冲平尾求飞机极曲线的修正方法简便实用，是切实可行的。   << 更多相关文摘 
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