【作者】 李大伟； 李桂娟； 刘彦森；

【Author】 LI Da-wei;LI Gui-juan;LIU Yan-sen;Science and Technology on Underwater Test and Control Laboratory;

【机构】 水下测控技术重点实验室；

【摘要】 针对增升机构在自由来流中的噪声特点,本文提出了利用计算流体力学耦合Ffowcs Williams-Hawkings声类比方程来获得模型声场及目标特性的数值研究方法,并提出了利用位于缝翼空腔内的边界层吹吸气技术来减小增升机构宽频噪声的控制手段。通过比较瞬时和平均流场可以发现,边界层吹吸气技术能够有效的稳定源自于缝翼前缘自由剪切层的涡量场及Lamb矢量场,并且能够用移除缝翼空腔内的二次分离流。计算结果显示,通过选择适当的控制参数,边界层吹吸气控制可以有效的抑制流场的压力颤振、速度颤振、湍流动能、涡量、Lamb矢量以及噪声等流场参数;该控制方法还明显改变了增升机构的远场目标特性。更多还原

【Abstract】 The flow field and sound radiation of a three component high lift configuration in free-flight is investigated through computational fluid dynamics simulations in conjunction with a Ffowcs Williams-Hawkings acoustics solver. The boundary layer blow and suction control method on the inner slat surface has been used to suppress the broadband noise generated by the high lift configuration. By the comparison of instantaneous and time averaged results, the boundary layer control can effectively stabilize the shear layer that originates from the leading edge of the slat by removing the secondary separation flow on the inner slat surface. When the suitable boundary layer blow control parameters have been chosen, the computation results show the fluctuating of the velocity and pressure, turbulence kinetic energy, vorticity and Lamb vector in the slat cove are suppressed by the boundary layer control. The strong reduction of noise level in far-field and the steadiness of flow field in the slat cove demonstrate that the boundary layer control method is an effective way to control the noise of the high lift configuration.更多还原