这篇论文用CMP和卡门涡街两个具体案例告诉你：没有万能代理模型，选架构要看流动的动力学特点，别用RMSE骗自己。
该论文测试了八种代理模型在两种瞬态流动上的表现：三维CMP浆料膜和二维卡门涡街。在CMP膜上，单次全场模型将累积壁面剪切应力误差控制在3.2%。在涡街中，潜变量自回归DeepONet保留了96%的脱落功率，而直接和单次模型几乎将其衰减为零。评估采用五个物理指标而非逐点RMSE，并发现不同动态特征需要不同架构。训练好的代理模型比有限元求解器快10^3到10^4倍。
No Free Lunch in Flow Surrogates under Time-Varying Boundary Conditions: A Two-Regime Study
A flow surrogate validated on a simple regime is often taken as evidence that the approach will carry to a richer one. We test this assumption on two transient flows under time-varying boundary conditions emulating the process startup: the three-dimensional slurry film in chemical-mechanical planarisation (CMP), a core semiconductor-manufacturing process, and the two-dimensional Karman vortex street (KVS) behind a cylinder. Eight surrogate models are compared on one shared evaluation pipeline, differing in whether they learn the full field or a latent representation, and whether they predict trajectories in one shot or step by step. No single architecture wins both regimes. On the film, a one-shot full-field model reconstructs the process-relevant cumulative wall shear stress to 3.2% relative error. On the wake, a latent autoregressive DeepONet retains 96% of the shedding power that direct and one-shot models damp to almost zero. The deciding axis is the treatment of time. The self-sustained wake requires the phase memory that autoregressive feedback provides, while the boundary-driven film rewards a direct map. Pointwise RMSE picks the wrong model in both regimes, so the evaluation scores five physical questions instead, the field, its structure, invented motion, amplitude, and timing. The trained surrogates answer queries $10^3$ to $10^4$ times faster than the finite-element solver, but the offline cost of the training simulations means they pay off from the first query beyond the training set for CMP and the third for the KVS. The choice of surrogate should follow the dynamical character of the target flow, and its validation should use failure-mode-resolved metrics, since neither the winning architecture nor its validation transfers.