基于NS/CFIE伴随方程的飞行器气动隐身综合优化

Integrated aerodynamic and stealth optimization of aircraft based on NS/CFIE adjoint equations

先进气动隐身综合设计技术是实现未来作战飞机高隐身、高机动、宽速域、远航程等技术指标的关键环节,基于跨学科耦合伴随思想,推导了气动隐身“耦合”伴随方程。首先基于Navier-Stokes方程构建流场伴随方程,进一步通过近场矢量乘和远场矢量乘两部分变分处理,以及雷达散射面积的变分,构建了基于多层快速多极子(MLFMA)算法的电磁伴随方程,结合自主研发的XSQP寻优框架与参数化建模技术,构建高可信度气动隐身综合优化技术平台。以某型飞翼布局为研究对象,进行气动隐身一体化测试。测试结果表明,所建立的伴随平台梯度计算精度较高,优化设计效率极高,能够为作战飞机气动隐身一体化设计提供有力的技术支撑。

Advanced integrated aerodynamic and stealth design technology is the key link to realize the technical indexes of future combat aircraft,such as high stealth,high maneuverability,wide speed range and long range.This study derives the“coupled”adjoint equation of aerodynamic stealth based on the idea of interdisciplinary coupling adjoint.First,the adjoint equation of the flow field is constructed based on the Navier-Stokes equation.Through the variational processing of near-field vector multiplication,far-field vector multiplication,and the radar scattering area,the adjoint equation based on MLFMA is then developed.The electromagnetic adjoint equation of the algorithm,combined with the independently developed XSQP optimization framework and parametric modeling technology,constructs a highly reliable aerodynamic stealth comprehensive optimization technology platform.Taking a certain flying wing layout as the research object,we conduct the aerodynamic stealth integration test.The test results show that both the gradient calculation accuracy of the established accompanying platform and the optimization design efficiency are high,providing strong technical support for the aerodynamic stealth integration design of combat aircraft.