A general use adjoint formulation for compressible and incompressible inviscid fluid dynamic optimization
A general use adjoint formulation for compressible and incompressible inviscid fluid dynamic optimization
复制标题
可压缩和不可压缩无粘流体动力学优化的通用伴随公式
DOI：
10.1016/j.compfluid.2018.11.011
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发表时间：
2019
影响因子：
2.8
通讯作者：
A. Dadone
中科院分区：
文献类型：
--
作者：
G. Caramia;A. Dadone
一个离散的伴随制定与特设流动求解器最近已经开发和测试跨音速无粘流优化问题。在本文中，制定扩展到各种可压缩流求解器以及求解不可压缩流。一个近似的，耗散流求解器被用来开发离散的准时间相关的伴随方程。设计问题采用渐进优化，即，一系列的操作，包含一个部分收敛的流的解决方案，其次是伴随解决方案，其次是优化步骤。该过程是使用一系列逐渐精细的网格进行的。灵敏度导数变化被限制以保持渐进过程的平滑性。首先，伴随方程与一个精确的内部流场求解器相结合，以测试一些涉及二维和三维超声速，跨音速，亚音速和不可压缩流的逆设计问题的方法。然后，以前的设计测试情况下重新计算耦合的扩展伴随配方与商业和开源流求解器，没有注意到任何相关的差异，在优化收敛历史。最后，不可压缩的设计测试情况下，成功地计算耦合的扩展伴随制定与商业求解不可压缩流。扩展的可压缩伴随公式似乎有广泛的应用，因为它允许使用不同的流动条件，不同的流动求解器，甚至不可压缩流的求解器进行准确和有效的设计优化。
A discrete adjoint formulation with an ad hoc flow solver has been recently developed and tested on transonic inviscid flow optimization problems. In the present paper the formulation is extended to various compressible flow solvers as well as to a solver for incompressible flows. An approximate, dissipative flow solver is used to develop the discrete quasi-time-dependent adjoint equations. The design problem employs a progressive optimization, i.e., a sequence of operations, containing a partially converged flow solution, followed by an adjoint solution followed by an optimization step. The procedure is performed using a sequence of progressively finer grids. The sensitivity derivative variations are limited to preserve the smoothness of the progressive procedure. First, the adjoint equations are coupled with an accurate in-house flow solver to test the approach on some inverse design problems involving two- and three-dimensional supersonic, transonic, subsonic and incompressible flows. Then, the previous design test cases are re-computed coupling the extended adjoint formulation with commercial and open source flow solvers, without noticing any relevant difference in the optimization convergence histories. Finally, incompressible design test cases are successfully computed coupling the extended adjoint formulation with a commercial solver for incompressible flows. The extended compressible adjoint formulation appears to have a wide application, insofar as it allows to perform accurate and efficient design optimization using different flow conditions, different flow solvers and even a solver for incompressible flows.