稳态神经 CFD 代理模型的跨域预训练
Cross-Domain Pretraining for Steady-State Neural CFD Surrogates
Anthony Zhou · Amir Barati Farimani · Shirley Ho · Rudy Morel
中文摘要
计算流体动力学(CFD)的神经代理模型有潜力通过加速仿真大幅推动工程创新。然而,神经代理模型的主要局限在于难以泛化到训练集之外的几何与应用场景,鉴于工程场景的多样性,这一问题尤为突出。当前做法是为每个具体应用生成新数据集,但这需要运行高成本数值求解器。本工作朝解决这一方向迈进了一步,研究了在不同几何、不同边界条件、不同保真度数据上联合训练的神经代理模型。结果表明,跨域预训练在零样本与少样本任务上均优于从零训练以及从领域专属专家模型迁移。具体而言,相比从零训练,微调跨域预训练模型在相同样本量下误差降低 2-3 倍,在相同误差下所需样本量减少 8 倍。该收益与具体网络架构无关,并随模型规模与预训练数据集多样性的提升而增强。进一步地,论文分析了跨域预训练在 CFD 代理模型中为何起作用以及如何起作用,结果表明直接将稳态数据集进行池化整合即足够且有效。鉴于 CFD 数据生成成本高昂,通过跨域预训练复用已有数据,将成为未来代理模型拓展新问题与新应用场景时极具价值的策略。
关键要点
- 01问题:神经 CFD 代理模型泛化能力不足,难以迁移到训练集之外的几何与应用场景,而为每个应用生成新数据集成本极高。
- 02方法:在不同几何、不同边界条件、不同保真度的稳态 CFD 数据上进行跨域联合预训练,随后在下游任务上微调。
- 03结果:相比从零训练,跨域预训练微调在相同样本量下误差降低 2-3 倍,达到相同误差仅需 1/8 的样本量。
- 04适用性:该收益与网络架构无关,并随模型规模与预训练数据集多样性的增加而提升。
- 05结论:直接池化整合稳态 CFD 数据集即足够有效,无需复杂组合策略,为复用高成本 CFD 数据提供可行路径。
解读
尚无解读。
原始英文摘要
arXiv:2610.10398v1 Announce Type: new Abstract: Neural surrogates for computational fluid dynamics (CFD) have the potential to greatly enhance engineering innovation through accelerating simulation. However, the primary limitation for neural surrogates is the lack of generalization to geometries and applications beyond the training set, which is significant given the diversity of engineering scenarios. Currently, this is addressed by generating a new dataset for a specific application; however, this requires running costly numerical solvers. In this work, we take a step toward addressing this by studying neural surrogates trained across different geometries, boundary conditions, and fidelities. We find that cross-domain pretraining improves zero- and few-shot performance on held-out datasets relative to both training from scratch and transferring from domain-specific experts. In particular, finetuning a pretrained, cross-domain model can achieve 2-3x lower errors at the same sample size and use 8x fewer samples to achieve the same error, compared to training from scratch. This benefit is architecture agnostic and improves with model size and pretraining dataset diversity. Furthermore, we study how and why cross-domain pretraining works in CFD surrogates, and find that simply pooling steady-state datasets is both sufficient and effective. Given the high cost of generating CFD data, leveraging existing datasets through cross-domain pretraining will likely be a valuable strategy as future surrogates expand to tackle new problems and use cases.