跨速域大后掠角近距耦合翼气动干扰特性

为研究亚声速、跨声速、超声速及高超声速跨速域条件下，某正常式布局飞行器的大后掠角前翼对尾翼气动特性的影响和机理，通过有限体积法求解雷诺平均Navier-Stokes方程，并采用Spalart-Allmaras湍流模型对具有大后掠角近距耦合翼的飞行器绕流场进行数值模拟。计算得出受前翼气动干扰影响时尾翼的升力系数、阻力系数随马赫数和攻角的变化规律，且根据尾翼表面压力系数分布规律和周围流场结构，分析前翼对尾翼的气动干扰机理。研究结果表明：在亚声速、跨声速条件下，大后掠角前翼产生的后脱涡会影响尾翼周围的流场，尤其是尾翼前缘的绕流场，使尾翼上下表面的压力差减小，尾翼的升力和阻力系数均减小；攻角越大，前翼产生的涡流强度越大，前翼对尾翼的下洗作用越强，尾翼的升力系数和阻力系数的减小量越大；随着马赫数的增大，前翼后脱涡逐渐变弱，前翼对尾翼的干扰影响也逐渐减弱。

Numerical Simulation of Aerodynamic Interference of Close-coupled Highly Swept-back Wings at Transonic Velocity

The paper investigates the aerodynamic interference of close-coupled highly swept-back wings to the tail wings at transonic velocity which is from subsonic velocity to hypersonic velocity. The numerical method is based on the Reynolds-averaged Navier-Stokes equations and finite volume method. The Spalart-Allmaras turbulence model is used to simulate the flow field around an air vehicle with close-coupled highly swept-back wings. The distributions of aerodynamic coefficients of tail at different Mach numbers and angles of attack under the influence of the front wing are given. The variation of surface pressure coefficient and the flow structure of tail are analyzed to figure out the aerodynamic interference mechanism. The results indicate that the flow field around tail is influenced greatly by the vortex from the highly swept-back wing under both subsonic and transonic flow conditions. The decrease in the pressure difference of upper and lower tail surfaces results in decreasing the lift coefficient and drag coefficient of tail. Besides, the greater the angle of attack is, the greater the vortex intensity is, and the greater the reductions of lift coefficient and drag coefficient of tail are. The influence of wing on tail decreases with the increase in Mach number.