异质凝结的动理论研究及在细颗粒物清除中的应用

项目名称： 异质凝结的动理论研究及在细颗粒物清除中的应用

项目编号： No.21476221

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 有机化学

项目作者： 罗喜胜

作者单位： 中国科学技术大学

项目金额： 86万元

中文摘要： 异质凝结是一种常见的相变过程，而这种常见的宏观现象却由复杂的微观物理过程决定。异质凝结在自然环境和工业生产中十分普遍，特别是近年来随着大气细颗粒物污染日益严重，异质凝结在工业细颗粒物去除中已成为一种新型有效的预处理手段。本申请拟从理论、数值和实验三方面来研究异质凝结的复杂机理，进而优化异质凝结促进细颗粒物清除的技术。首先，通过构建异质凝结的动理论模型，修正稳态成核率公式，发展多相流数值模拟方法，从微观上研究凝结的启动过程，计算液滴在颗粒表面的增长率，并模拟颗粒上凝结的完整过程。其次，采用数值方法，从宏观上系统研究外界条件对凝结的影响，进而考察对颗粒清除效率的影响。最后，结合机理性和系统性实验，模拟利用异质凝结促进细颗粒物清除过程，提出优化方案。通过该研究，可以揭示异质凝结的现象和规律，也可为实际清除细颗粒物技术发展与优化提供理论基础。

中文关键词： 异质凝结；细颗粒清除；动理论；参数分析；优化方案

英文摘要： Heterogeneous condensation is a very common phenomenon in atmospheric physics, gas cleaning technology, and multiphase flow, which is determined by a complicated microphysical process. Especially in the separation of submicron particle from gas, the heterogeneous condensation as a preconditioning technique can improve the particle removal efficiency substantially. In this proposal, we shall study the complex mechanism of heterogeneous condensation by means of theory, computation and experiment, and optimize the particle removal technology which uses heterogeneous condensation. Firstly, a new kinetic model for heterogeneous condensation is proposed and is used to revise the formula of steady-state nucleation rate, to simulate the start-up process of condensation, and to calculate the growth rate of the droplet on particle. The new kinetic model can also be used to develop the physical model in the numerical simulation of multiphase flow. Then, for the technical optimization, we shall use the numerical simulation and experimental observation to investigate the effects of the ambient conditions and the particle properties on the particle removal efficiency. Finally, an optimized scheme for the particle removal technology using heterogeneous condensation will be developed. It is expected that our study will give a deep insight into the mechanism of heterogeneous condensation, and also provide a theoretical basis for the technical optimization in the practical particle removal.

英文关键词： heterogeneous condensation;fine particles removal;kinetic model;parametric analysis;optimization