Three dimensional radar cross section geometric sensitivity calculation based on discrete adjoint equation

被引:0
|
作者
Zhou L. [1 ]
Huang J. [2 ]
Gao Z. [1 ]
机构
[1] School of Aeronautics, Northwestern Polytechnical University, Xi'an
[2] China Aerodynamics Research and Development Center, Mianyang
关键词
Discrete adjoint equation; Gradient calculation; Method of moment; Multilevel fast multipole algorithm; Radar cross section;
D O I
10.7527/S1000-6893.2019.23361
中图分类号
学科分类号
摘要
A Radar Cross Section (RCS) gradient calculation method based on adjoint equation of Maxwell integral equation is proposed. This method aims to overcome the high cost and low efficiency in the traditional finite difference calculation method. The adjoint method can obtain the gradients of all design variables by one radar cross-section solution and one adjoint solution. The required calculation amount of the gradient solution is basically independent of the number of design variables. The form of adjoint equation is similar to the original equation, and can be solved by the Method of Moment (MOM) and Multilevel Fast Multipole Algorithm (MLFMA). The calculation and storage amount in solving adjoint equation is basically the same as the calculation of RCS. By adopting the double ogive model and a missile model, two test cases are adopted to ve-rify the reliability and precision of the adjoint method. Gradients calculated based on the adjoint method of MOM and MLFMA are compared with the finite difference results. Numerical results prove the accuracy of the adjoint method, and demonstrate that it can be applied in complex shapes, providing a basis for the construction of gradient-based aerodynamics-stealth optimization framework. © 2020, Press of Chinese Journal of Aeronautics. All right reserved.
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共 29 条
  • [1] Wang R., Yan M., Bai P., Et al., Optimization design of aerodynamics and stealth for a flying-wing UAV platf-orm, Acta Aeronautica et Astronautica Sinica, 38, pp. 77-84, (2017)
  • [2] Jiang X.W., Zhao Q.J., Meng C., Effect of helicopter rotor blade shape on its radar signal characteristics, Acta Aeronautica et Astronautica Sinica, 35, 11, pp. 3123-3136, (2014)
  • [3] Ruan Y.Z., Radar Cross Section and Stealth Technol-ogy, pp. 115-120, (1998)
  • [4] Sang J.H., Low-Observable Technologies of Aircraft, pp. 321-334, (2012)
  • [5] Wang M.L., Gao Z.H., Xia L., Influence of aerodynamic and stealth performance conputation precision on aircraft optimization design, Flight Dynamics, 27, 6, pp. 14-17, (2009)
  • [6] Zhang B.Q., Luo L., Chen Z.L., Et al., On stealth airfoil design for flying wing configuration, Acta Aeronautica et Astronautica Sinica, 35, 4, pp. 957-967, (2014)
  • [7] Harrington R.F., Harrington J.L., Field Computation by Moment Methods, pp. 15-20, (1993)
  • [8] Coifman R., Rokhlin V., Wandzura S., The fast multipole method for the wave equation: A pedestrian prescription, IEEE Antennas and Propagation Magazine, 35, 3, pp. 7-12, (1993)
  • [9] Gao Z.H., Xia L., Li T., Et al., Investigation into collaborative optimization design techniques of aircraft aerodynamics and stealth performances, Aircraft Design, 3, pp. 1-5, (2003)
  • [10] Xia L., Zhang X., Yang M.H., Et al., Airfoil aerodynamic stealth integrated design for a flying wing configuration, Journal of Northwestern Polytechnical University, 35, 5, pp. 821-826, (2017)