Computational Fluid Dynamics (CFD) is a major sub-field of engineering. Corresponding flow simulations are typically characterized by heavy computational resource requirements. Often, very fine and complex meshes are required to resolve physical effects in an appropriate manner. Since all CFD algorithms scale at least linearly with the size of the underlying mesh discretization, finding an optimal mesh is key for computational efficiency. One methodology used to find optimal meshes is goal-oriented adaptive mesh refinement. However, this is typically computationally demanding and only available in a limited number of tools. Within this contribution, we adopt a machine learning approach to identify optimal mesh densities. We generate optimized meshes using classical methodologies and propose to train a convolutional network predicting optimal mesh densities given arbitrary geometries. The proposed concept is validated along 2d wind tunnel simulations with more than 60,000 simulations. Using a training set of 20,000 simulations we achieve accuracies of more than 98.7%. Corresponding predictions of optimal meshes can be used as input for any mesh generation and CFD tool. Thus without complex computations, any CFD engineer can start his predictions from a high quality mesh.
翻译:计算液流动力(CFD)是一个主要的工程领域。相应的流量模拟通常具有大量计算资源要求的特点。通常需要非常精细和复杂的 meshes 才能以适当的方式解决物理效应。由于所有 CFD 算法的尺度至少线性与底部网状分解的大小不同,因此,找到一个最佳网点是计算效率的关键。一种用于寻找最佳 meshes 的方法是目标导向的适应性调整改进。然而,这通常是计算要求很高,并且只能在数量有限的工具中提供。在此贡献中,我们采用机器学习方法来确定最佳的网点密度。我们利用古典方法产生优化的网点,并提议培训一个预测最佳网点密度的进化网络,根据任意的地理外观,预测最佳网点密度。拟议的概念与2个风道模拟一起得到验证,有6万多个模拟。使用一套20 000个模拟的培训,我们实现了98.7%以上的理解度。对最佳模件的预测可以作为任何MESD 的高级预测的输入,任何复杂的计算工具都可以从CFD 和CFD。