论文标题
GPU加速计算流体动力学求解器，用于评估剪切驱动的室内气流和通过尺度分辨的模拟传播
A GPU-accelerated computational fluid dynamics solver for assessing shear-driven indoor airflow and virus transmission by scale-resolved simulations
论文作者
论文摘要
我们探讨了MATLAB在剪切驱动室内气流的3D计算流体动力学（CFD）中的适用性。提出了一个新的分布量表大型模拟（LES）求解器，标题为DNSlabib，用于使用图形处理单元（GPU）MATLAB。首先针对另一个CFD软件（OpenFOAM）验证求解器。接下来，我们在三种等温室内通风配置中演示了求解器性能，并在Covid-19的空中传播中讨论了结果。在这些情况下，在低（0.1 m/s）和高（1 m/s）的气流速率对应于$ re = 5000 $和$ re = 50000 $的情况下，对通风进行了研究。当房间从陈旧的高co $ _2 $ content air上清空时，对室内公司的分析进行了分析。我们估计三种不同房间几何的每小时空气变化（ACH）值（ACH）值，并表明3D CFD模拟的数值估计值可能会差异80-150％（$ re = 50000 $）和75-140％（$ re = 5000 $）与理论ACH值的75-140％（$ re = 5000 $）基于完美的混合假设。此外，对CO $ _2 $概率分布（PDFS）的分析表明，新鲜空气在室内的分布相对不均匀。最后，利用时间依赖性的井瑞利分析，提供了一个示例，说明累积感染风险在开始通气后迅速降低。对于较低的通风率（ACH = 3.4-6.3），平均感染风险降低了2倍，而较高的通风率（ACH = 37-64）降低了。结果表明，DNSlabib在气流预测的各种未来发展中具有很高的潜力。
We explore the applicability of MATLAB for 3D computational fluid dynamics (CFD) of shear-driven indoor airflows. A new scale-resolving, large-eddy simulation (LES) solver titled DNSLABIB is proposed for MATLAB utilizing graphics processing units (GPUs). The solver is first validated against another CFD software (OpenFOAM). Next, we demonstrate the solver performance in three isothermal indoor ventilation configurations and the results are discussed in the context of airborne transmission of COVID-19. Ventilation in these cases is studied at both low (0.1 m/s) and high (1 m/s) airflow rates corresponding to $Re=5000$ and $Re=50000$. An analysis of the indoor CO$_2$ concentration is carried out as the room is emptied from stale, high CO$_2$ content air. We estimate the air changes per hour (ACH) values for three different room geometries and show that the numerical estimates from 3D CFD simulations may differ by 80-150 % ($Re=50000$) and 75-140 % ($Re=5000$) from the theoretical ACH value based on the perfect mixing assumption. Additionally, the analysis of the CO$_2$ probability distributions (PDFs) indicates a relatively non-uniform distribution of fresh air indoors. Finally, utilizing a time-dependent Wells-Riley analysis, an example is provided on the growth of the cumulative infection risk being reduced rapidly after the ventilation is started. The average infection risk is shown to reduce by a factor of 2 for lower ventilation rates (ACH=3.4-6.3) and 10 for the higher ventilation rates (ACH=37-64). The results indicate a high potential for DNSLABIB in various future developments on airflow prediction.
