Scholar - SciOpen

Significance

The development of generalizable, data-driven aerodynamic analysis models capable of real-time, high-fidelity prediction for arbitrary shapes under any flight condition represents a key technology for next-generation rapid intelligent aircraft design. Conventional aerodynamic optimization in preliminary design phases suffers from a critical dilemma: high-fidelity Computational Fluid Dynamics (CFD) is computationally prohibitive, while lower-fidelity methods lack sufficient accuracy. This severely hinders the rapid exploration of design spaces under varying constraints and objective functions. AI-driven approaches offer transformative potential, overcoming the limitations of expert-dependent, iterative traditional methods characterized by long cycles, parametric limitations, and difficulty in generating initial concepts. Realizing robust, generalizable aerodynamic models promises not only dramatic efficiency gains and reduced reliance on costly wind tunnel testing but also enables true multidisciplinary design optimization (MDO), integrating aerodynamics, structures, and control. This convergence of AI and aerospace engineering holds significant strategic value for enhancing national competitiveness in advanced vehicle design.

Progress

This review addressed the core challenge hindering generalizable data-driven aerodynamic models, the curse of dimensionality. Building models generalizable across vast geometric and operational spaces typically demands prohibitively large training datasets. Our research tackled this through two synergistic advancements in geometric representation and model building, enabling effective models trained on ~100,000 CFD samples for airfoil and wing optimization:

Advanced Geometric Parameterization: We moved beyond traditional methods (e.g., CST, Hicks-Henne, FFD) by employing data-driven modal techniques for efficient design space characterization. Reformulating the active geometric design space by extracting dominant modes from meaningful training shapes drastically reduced dimensionality.

Data-Driven Flow Modeling & Optimization: Deep learning models were integrated to learn the mapping between the reduced geometric parameters and the aerodynamic coefficients or flow fields, enabling near-instantaneous predictions. Gradient-based optimization algorithms were prioritized due to their significantly faster convergence rates, crucial for rapid design cycles. Gradient-free methods require careful consideration to manage computational expense.

This combined approach of efficient geometric encoding and data-driven aerodynamic prediction successfully enabled rapid optimization of airfoil and wing configurations within the constructed framework.

Conclusions and Prospects

This review demonstrated the significant potential of data-driven methodologies, combining advanced geometric parameterization and aerodynamic modeling techniques, to overcome the curse of dimensionality and achieve rapid aerodynamic optimization for fundamental components like airfoils and wings. Validation using datasets on the order of 100,000 CFD samples confirms the feasibility of building practical models enabling near real-time analysis and design iteration.

However, the field remains in its early stages. Key challenges and future directions include:

(1) Generalization Limits: Current models, while effective for isolated components like wings or airfoils within trained domains, lack robust generalization capabilities, especially for completely novel configurations or complex multi-component interactions (e.g., wing-body junctions, nacelle integration).

(2) Complex Configuration Optimization: Extending rapid optimization to full aircraft configurations, necessitating models that efficiently capture the complex aerodynamic couplings between wings, fuselage, and propulsion systems, is a critical next frontier.

(3) Model Robustness & Uncertainty: Enhancing model reliability across wider flight envelopes (e.g., transonic regimes, high angles of attack) and incorporating uncertainty quantification are essential for engineering applications.

The integration of AI and data science with aerodynamic design is rapidly evolving. Overcoming the current limitations, particularly regarding complex configurations and generalization, will unlock the full potential of data-driven approaches, revolutionizing the speed, cost-effectiveness, and innovation capacity of future aircraft design processes. The strategic importance of mastering this convergence for advancing aerospace capabilities cannot be overstated.

Aerodynamic shape optimization of hypersonic vehicles is critically important yet profoundly challenging. The difficulties arise from the need to manage multiple competing objectives, complex three-dimensional geometries, and the extreme computational cost of high-fidelity aerodynamic simulations across subsonic, transonic, and hypersonic regimes. Despite recent advances, an effective global optimization strategy for hypersonic aircraft design remains limited, largely hindered by the curse of dimensionality. To remove this barrier, we propose a data-driven generative nonlinear shape parameterization framework for efficient aerodynamic design of hypersonic aircraft. This framework begins by constructing diverse hypersonic aircraft shapes that cover the feasible sub-domains of a high-dimensional design space. A linear dimension reduction method is used to transform the high-dimensional point-cloud database to a low-dimensional modal space. Subsequently, a nonlinear generative model is trained to learn the statistical distribution feature of the linear mode coefficients. The resulting generative latent space provides an efficient, low-dimensional, and expressive parameterization of aerodynamic shapes. The proposed method is validated in both single-point and multi-point optimization of hypersonic aircraft, demonstrating superior efficiency and effectiveness compared with conventional parameterization approaches. This study presents an efficient roadmap for aerodynamic shape parameterization and global optimization of next-generation aircraft.