The application of the continuous adjoint method has been conducted on a 2D hypersonic inlet design optimization. The 2D hypersonic inlet is an inviscid curved compression configuration designed based on characteristics method. The external compression surface has been parameterized through the free form deformation (FFD) method. The viscous mass flow rate of the inlet has been taken as the optimization objective. The flow governing equations and the continuous adjoint equations have been solved on three different grids to analyze the external compression surface sensitivity contrastively. The results indicate that the external compression surface sensitivity has a strong boundary layer mesh dependence. The objective gradients obtained by the continuous adjoint method are credible according to the comparison with the finite difference method. The BFGS algorithm has been adopted
and the optimization results show that the incident shock wave seals the external flow at the cowl. This behavior increases the inlet mass flow rate by 6.3%
and the integrated performances of the inlet have been promoted. The maximum normal displacement of the external compression surface is 5.6 mm. Based on the optimal results
the adjoint method could be applied successfully in hypersonic inlet design optimizations.
关键词
Keywords
references
HEISER W H, PRATT D T. Hypersonic airbreathing propulsion[M]. Washington:AIAA, 1994.
WU Y C, HE Y Y, HE W, et al. Progress in airframe-propulsion integration technology of air-breathing hypersonic vehicle[J]. Acta Aeronautica et Astronautica Sinica, 2015, 36(1):245-260.(in Chinese)
PIRONNEAU O. On optimum profiles in Stokes flow[J]. Journal of Fluid Mechanics, 1973, 59(1):117-128.
JAMESON A. Aerodynamic design via control theory[J]. Journal of Scientific Computing, 1988, 3(3):233-260.
REUTHER J, JAMESON A. Supersonic wing and wing-body shape optimization using an adjoint formulation[R]. NASA 1995-13035.
REUTHER J, JAMESON A, FARMER J, et al. Aerodynamic shape optimization of complex aircraft configurations via an adjoint formulation[C ] //34th AIAA Aerospace Sciences Meeting. Reno, NV, AIAA, 1996. DOI: 10.2514/6.1996-94
JAMESON A, ALONSO J J, REUTHER J J. Aerodynamic shape optimization techniques based on control theory[R]. AIAA 1998-2538.
ANDERSON W K, VENKATAKRISHNAN V. Aerodynamic design optimization on unstructured grids with a continuous adjoint formulation[J]. Computers Fluids, 1999, 28(4):443-480.
GILES M B, PIERCE N A. Adjoint equations in CFD: duality, boundary conditions and solution behaviour[R]. AIAA 1997-1850.
GILES M B, PIERCE N A. On the properties of solutions of the adjoint Euler equations[C]//6th ICFD Conference on Numerical Methods for Fluid Dynamics, Oxford, UK, 1998.
DURAISAMY K, ALONSO J J, PALACIOS F, et al. Error estimation for high speed flows using continuous and discrete adjoints[C ] //48th AIAA Aerospace Sciences Meeting, Orlando, FL, AIAA, 2010. DOI: 10.2514/6.2010-128
WANG Q, DURAISAMY K, ALONSO J J, et al. Risk assessment of scramjet unstart using adjoint-based sampling methods[J]. AIAA Journal, 2012, 50(3):581-592.
CUI P C, DENG Y Q, TANG J, et al. Adjoint-equations-based grid adaptation and error correction[J]. Acta Aeronautica et Astronautica Sinica, 2016, 37(10):2992-3002.(in Chinese)
BAI J Q, CHEN S, HUA J, et al. Transonic wing aerodynamic design based on continuous adjoint method and free form deform technique[J]. Acta Aerodynamica Sinica, 2014, 32(6):820-33.(in Chinese)
COPELAND S R. A continuous adjoint formulation for hypersonic flows in thermochemical nonequilibrium[D]. Stanford University, 2015.
KLINE H, PALACIOS F, ECONOMON T D, et al. Adjoint-based optimization of a hypersonic inlet[C ] //22nd AIAA Computational Fluid Dynamics Conference, Dallas, TX, AIAA, 2015. DOI: 10.2514/6.2015-3060
KLINE H L, ECONOMON T D, ALONSO J J. Multi-objective optimization of a hypersonic inlet using generalized outflow boundary conditions in the continuous adjoint method[C]//54th AIAA Aerospace Sciences Meeting, San Diego, CA, AIAA, 2016.
Wei F. Investivation on design methodology for inward turning inlet based on the rotional method of characteristics[D]. Changsha: National Univsesity of Defense Techology, 2012.(in Chinese)