Department of Aerospace Science and Technology, Politecnico di Milano, Via La Masa, 34 20156 Milano, Italy.
J Biomech. 2022 Jun;138:111100. doi: 10.1016/j.jbiomech.2022.111100. Epub 2022 Apr 27.
Computational fluid dynamics of the air flow in the human nasal cavities, starting from patient-specific Computer Tomography (CT) scans, is an important tool for diagnostics and surgery planning. However, a complete and systematic assessment of the influence of the main modelling assumptions is still lacking. In designing such simulations, choosing the discretization scheme, which is the main subject of the present work, is an often overlooked decision of primary importance. We use a comparison framework to quantify the effects of the major design choices. The reconstructed airways of a healthy, representative adult patient are used to set up a computational study where such effects are systematically measured. It is found that the choice of the numerical scheme is the most important aspect, although all varied parameters impact the solution noticeably. For a physiologically meaningful flow rate, changes of the global pressure drop up to more than 50% are observed; locally, velocity differences can become extremely significant. Our results call for an improved standard in the description of this type of numerical studies, where way too often the order of accuracy of the numerical scheme is not mentioned.
从患者特定的计算机断层扫描 (CT) 扫描开始，对人体鼻腔内气流进行计算流体动力学分析是诊断和手术规划的重要工具。然而，对于主要建模假设的影响，仍然缺乏完整和系统的评估。在设计此类模拟时，选择离散化方案（本工作的主要主题）是一个经常被忽视但至关重要的决策。我们使用比较框架来量化主要设计选择的影响。使用健康、有代表性的成年患者的重建气道来建立一个计算研究，系统地测量这些影响。结果表明，数值方案的选择是最重要的方面，尽管所有变化的参数都明显影响解。对于生理上有意义的流速，观察到全局压降的变化高达 50%以上；在局部，速度差异可能变得非常显著。我们的结果呼吁在这种类型的数值研究的描述中提高标准，在这种研究中，数值方案的精度顺序通常没有被提及。
