论文标题
湍流模型中贝叶斯不确定性定量的自适应模型改进方法
Adaptive Model Refinement Approach for Bayesian Uncertainty Quantification in Turbulence Model
论文作者
论文摘要
在过去的几年中,贝叶斯不确定性量化技术已在湍流建模方面已建立。但是,在高维设计空间中构建贝叶斯推断的全球精确替代模型在计算上昂贵,这限制了复杂流程配置的不确定性量化。这项工作提出了从分层抽样和遗传采样的借用思想,一种自适应模型改进方法,该方法集中在渐近地提高高素质密度区域中替代模型的局部准确性,并通过自适应附加的贴上模型评估点。为了实现这一目标,提出了对遗传拉丁超立方体抽样的修改,然后集成到贝叶斯框架中。通过二维热源反演问题及其扩展到高维设计空间,证明了所提出方法的有效性和效率。与先前的方法相比,自适应模型改进方法具有使用更少的评估点获得更可靠的推理结果的能力。最后,将方法应用于轴对称跨通心凸起流量的Mentric不确定性定量,并提供令人信服的数值结果。
The Bayesian uncertainty quantification technique has become well established in turbulence modeling over the past few years. However, it is computationally expensive to construct a globally accurate surrogate model for Bayesian inference in a high-dimensional design space, which limits uncertainty quantification for complex flow configurations. Borrowing ideas from stratified sampling and inherited sampling, an adaptive model refinement approach is proposed in this work, which concentrates on asymptotically improving the local accuracy of the surrogate model in the high-posterior-density region by adaptively appending model evaluation points. To achieve this goal, a modification of inherited Latin hypercube sampling is proposed and then integrated into the Bayesian framework. The effectiveness and efficiency of the proposed approach are demonstrated through a two-dimensional heat source inversion problem and its extension to a high-dimensional design space. Compared with the prior-based method, the adaptive model refinement approach has the ability to obtain more reliable inference results using fewer evaluation points. Finally, the approach is applied to parametric uncertainty quantification of the Menter shear-stress transport turbulence model for an axisymmetric transonic bump flow and provides convincing numerical results.