Aerodynamic Shape Optimization of Natural-Laminar-Flow Wing Using Surrogate-Based Approach
Aerodynamic Shape Optimization of Natural-Laminar-Flow Wing Using Surrogate-Based Approach
复制标题
使用基于代理的方法优化自然层流机翼的气动形状
DOI：
10.2514/1.j056661
复制
发表时间：
2018-07-01
期刊：
影响因子：
2.5
通讯作者：
Song, Wen-Ping
中科院分区：
文献类型：
--
作者：
Han, Zhong-Hua;Chen, Jing;Song, Wen-Ping
跨音速自然层流后掠机翼的气动外形优化仍然具有挑战性。这一困难与层流-湍流转捩的可靠预测以及粘性阻力和波阻的合理折衷有关。本文提出了一种基于代理模型的高效全局优化方法来解决这个问题。雷诺平均Navier-Stokes流解算器通过全e（N）方法进行自动转捩预测，其中双N因子分别用于Tollmien-Schlichting和横流不稳定性。该优化器是基于克里金代理模型和并行填充采样方法。用于中短程运输机的基线自然层流机翼是在巡航马赫数0.75时设计的。然后，阻力最小化与多达42个设计变量进行，并显着减阻（8.79%）已实现。对优化后的机翼进行了详细的分析，结果表明，减阻主要来自于机翼上表面激波的减弱和机翼下表面层流的扩展，而层流的扩展是通过抑制机翼下表面的横流不稳定性实现的。研究了优化机翼的鲁棒性，并进一步进行了多点优化，以提高对马赫数变化的鲁棒性。结果表明，基于代理优化的跨音速自然层流机翼气动外形优化是可行和有效的。
Aerodynamic shape optimization of a swept natural-laminar-flow wing in the transonic regime is still challenging. The difficulty is associated with reliable prediction of laminar-turbulence transition and reasonable compromise of viscous and wave drags. This paper proposes to use efficient global optimization based on surrogate models to address this problem. The Reynolds-averaged Navier-Stokes flow solver features automatic transition prediction via a full e(N) method, in which dual N factors are used for Tollmien-Schlichting and crossflow instabilities, respectively. The optimizer is based on the kriging surrogate model and parallel infill-sampling method. The baseline natural-laminar-flow wing for short- and medium-range transport aircraft is designed at a cruise Mach number 0.75. Then, drag minimization with up to 42 design variables is carried out, and significant drag reduction (8.79%) has been achieved. A close examination of the optimal wing shows that the drag reduction mainly comes from shock-wave weakening on the upper surface and laminar flow extending via suppression of crossflow instability on the lower surface. Robustness of the optimal wing is investigated, and multipoint optimization is further exercised to improve the robustness to the Mach number variation. It is demonstrated that surrogate-based optimization is feasible and effective for aerodynamic shape optimization of transonic natural-laminar-flow wings.