圆柱单孔高频压力探针测量高亚音速二维周期流场的方法

本文详细介绍了作者发展的圆柱单孔高频压力探针测量高亚音速二维周期性流场的方法。该方法简化了压缩性影响的修正 ,测量时置探针于九个方位角。它已被成功地应用于单。

流场中周期加肋圆柱壳受激振动的能量流输入特性

以一水下无限长周期加肋圆柱壳受迫振动的能量流输入为研究对象,分别用Flügge方程和Helmholtz方程建立壳体及声场的波运动方程,考虑肋骨的四种作用力和力矩,探讨了外流场对加肋圆柱壳受激振动输入能量流的影响,得出了外流场可以抑制系统能量流输入、水下加肋圆柱壳比充液加肋圆柱壳能量流输入弱的结论。

压气机平面叶栅试验台中尾板调节的数值研究

针对压气机平面叶栅试验台中尾板影响叶栅出口流场周期性的特征,以包含高亚音静子叶栅的全尺寸叶栅试验台为研究对象,数值研究了尾板长度和角度改变时叶栅出口流场的周期性变化情况。结果表明:相同叶栅进出口压比情况下,尾板越长,叶栅进口马赫数越高;在高亚音马赫数进口情况下,不同进气攻角下的压气机叶栅流场在不同尾板长度下都保持较好的周期性;在较低亚音马赫数进口情况下,选取较长尾板并进行角度调节有利于改进不同攻角下叶栅流场的周期性。

Oscillating Propagation of Kink in Nondissipative Frenkel-Kontorova Chain Due to External DC Force

We report the oscillating propagation of kink in a nondissipative Frenkel-Kontorova （FK） chain driven by external DC force, which is different from the usual propagation of localized modes with equal speed. When the kink moves in the opposite direction of the external DC force, the kink will be accelerated and the potential of the FK chain in the external force field is transformed to be the kinetic energy of the kink. If the kink reaches the boundary of the FK chain, the kink will be bounced back and moves in the opposite direction, then the kink will be decelerated gradually and the kinetic energy of the kink ＆ transformed to be the potential of the FK chain in the external force field. If the speed of the kink reaches zero, the kink will move in the opposite direction again driven by the external DC force, and a new oscillating cycle begins. Simulation result demonstrates exactly the transformation between the kinetic energy of the kink and the potential of the FK chain in the external force field. The interesting energy exchange is induced by the special topology of kinks, and other localized modes, such as breathers and envelope solitons, have no the interesting phenomenon.

开槽尾流板对跨声速涡轮平面叶栅流场影响的实验

采用数值计算和实验相结合的方式研究了开槽尾流板对跨声速涡轮平面叶栅流场周期性的影响。通过数值计算研究了不同开孔率(10%、15%、30%、50%)和偏转角度(70°、71°、72°)下尾流板对叶片表面及叶栅流道出口压力分布的影响,并通过实验验证了尾流板对流道出口流场周期性的改善作用。结果表明:无尾流板时叶片表面压力分布明显偏离周期性计算结果,且流道出口压力分布的周期性误差较大;尾流板偏转角度和开孔率会影响叶片表面及叶栅流道出口的压力分布,适当调节尾流板参数能改善流场周期性;安装开孔率为50%,偏转角度为70°的尾流板时各流道出口的压力分布一致性最好且最接近周期性计算结果,计算和实验结果的周期性误差较无尾流板时分别降低47.6%和28.1%。