ANOVA results for SNR related to δ<i>L/D.</i>

This research focuses on optimizing the design of dimples on a Blended-Wing-Body (BWB) airframe to enhance aerodynamic efficiency. Dimples serve as a passive flow control method intended to improve aerodynamic properties. Employing the Design of Experiments (DOE) framework and utilizing the Taguchi method, we examined five dimple design variables across three distinct levels. These variables included dimple placement, indentation depth, diameter, spacing between dimples, and the number of dimple rows on the BWB wing. An L18 orthogonal array (OA) was implemented to assess the impact of these variables on the drag coefficient (CD), lift coefficient (CL), and lift-to-drag ratio (L/D), which were used as performance metrics. High-fidelity Computational Fluid Dynamics (CFD) simulations were conducted for each of the eighteen configurations outlined by the L18 OA, across angles of attack ranging from 0° to 8°. Signal-to-Noise Ratio (SNR) analysis and Pareto Analysis of Variance (ANOVA) revealed that the dimple diameter had the most significant impact on both CD and L/D, contributing 35.19% and 40%, respectively, while the indentation depth showed the least influence. The study identified an optimal combination of design variables (A1B1C1D3E3), which minimizes CD and maximizes L/D. This work provides actionable guidelines for dimple design as a passive flow control method in aerospace applications.本研究聚焦于优化混合机翼机身（Blended-Wing-Body, BWB）的凹坑设计，以提升气动效率。凹坑作为一种被动流动控制手段，旨在改善气动特性。本研究采用试验设计（Design of Experiments, DOE）框架并结合田口方法，针对5个凹坑设计变量开展三水平参数分析，所涉变量包括凹坑布置位置、凹陷深度、直径、凹坑间距以及BWB机翼上的凹坑排数。研究采用L18正交表（Orthogonal Array, OA），以阻力系数（Drag Coefficient, CD）、升力系数（Lift Coefficient, CL）及升阻比（Lift-to-Drag Ratio, L/D）作为性能评价指标，考察各变量对上述指标的影响。针对L18正交表涵盖的18种构型，本研究在0°至8°的攻角范围内开展了高精度计算流体力学（Computational Fluid Dynamics, CFD）仿真。通过信噪比（Signal-to-Noise Ratio, SNR）分析与帕累托方差分析（Analysis of Variance, ANOVA）可知，凹坑直径对CD和L/D的影响最为显著，贡献率分别达35.19%与40%，而凹陷深度的影响最弱。本研究确定了可最小化CD并最大化L/D的最优设计变量组合（A1B1C1D3E3）。本研究可为航空航天领域中作为被动流动控制手段的凹坑设计提供可操作的设计指导准则。