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为了提高翼伞的飞行性能,需要研究伞衣织物透气性对翼伞气动特性的影响。使用不可压雷诺时均Navier-Stokes(RANS)方程模拟伞衣外部流场,建立了包含附加动量源项的多孔介质域控制方程模拟伞衣,对2种透气性材料模型和无透气性影响传统模型的气动特性和流场分布进行了二维和三维定常数值模拟。数值结果表明,求解多孔介质域控制方程可以得到较准确的伞衣透气速度,伞衣表面的湍流度急剧增加;使用较大透气量材料制作伞衣时,升力系数大幅下降,阻力系数大幅上升,同时会造成内腔泄压影响翼伞的外形保持;使用微透气量材料制作伞衣时,升力系数在小迎角时小于不透气模型,在大迎角时大于不透气模型,较小的透气速度能在大迎角时延缓边界层分离。
In order to improve the flight performance of the wing parachute, it is necessary to study the influence of the air permeability of the parachute fabric on the wing aerodynamic characteristics. The non-reusable Navier-Stokes (RANS) equations were used to simulate the external flow field of the canopy and the porous media field governing equation simulation parachute was established with additional momentum source. The effects of two kinds of air-permeable material models and non-air permeability on the traditional The aerodynamic characteristics and flow field distribution of the model are simulated by two-dimensional and three-dimensional numerical simulations. The numerical results show that the governing equation of porous media can get a more accurate ventilation rate of the umbrella canopy and the turbulence degree of the canopy surface increases sharply. When using a larger air permeability material to make the umbrella canopy, the lift coefficient decreases sharply and the drag coefficient increases sharply, At the same time, lumen pressure relief will affect the appearance of the wing umbrella. When using the micro-air-permeable material to make the umbrella canopy, the lift coefficient is smaller than the airtight model at small angle of attack and larger than the airtight model at high angle of attack, Velocity can delay the boundary layer separation at high angles of attack.