Abstract In this paper, we present a methodology for simulating nanoparticle formation in a turbulent flow by coupling Direct Numerical Simulation (DNS) and population balance modelling. The population balance equation (PBE) is solved via a discretisation method employing a composite grid that provides sufficient detail over the wide range of particle sizes reached during the precipitation process. The coupled DNS/PBE approach captures accurately the strong interaction between the dynamics of turbulent mixing and particle formation processes. It also allows the calculation of the particle size distribution (PSD) of the product and enables an investigation on how it is controlled by turbulent mixing. Finally, it provides the statistics of kinetic processes and their timescales so that further analysis can be performed. The methodology is applied to the simulation of experiments of hydrodynamics and nanoparticle precipitation in a T-mixer (Schwertfirm et al., Int. J. of Heat and Fluid Flow 28, pp. 1429–1442; Schwarzer et al., Chem. Eng. Sci. 61, pp. 167–181), and the agreement with the experimental results is very good.

中文翻译：

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一种耦合 DNS 和离散人口平衡以模拟湍流降水的方法

摘要 在本文中，我们提出了一种通过耦合直接数值模拟 (DNS) 和种群平衡建模来模拟湍流中纳米颗粒形成的方法。人口平衡方程 (PBE) 是通过离散化方法求解的，该方法采用复合网格，该网格提供了在降水过程中达到的广泛粒径范围内的足够详细信息。耦合的 DNS/PBE 方法准确地捕捉了湍流混合动力学和粒子形成过程之间的强相互作用。它还允许计算产品的粒度分布 (PSD)，并可以研究如何通过湍流混合来控制它。最后，它提供了动力学过程及其时间尺度的统计数据，以便可以进行进一步的分析。