波纹板阻火器微通道火焰淬熄精准数学模型的研究

The crimped ribbon flame arrester, which has been widely used for supersonic explosion-proof and explosion suppression, is an indispensable apparatus for safe production in the chemical industry. The flame arrester is firstly designed empirically and then verified experimentally by the traditional design method. However, this method is blind, unsafe, costly and time-consuming. Although the method of numerical simulation has the features of saving money and fast returns, its reliability and accuracy are dependent upon the mathematical model. In this project, the accurate mathematical model that include fluid flow at elevated temperature, violent combustion reactions, heat transfer (i.e., including heat convection, conduction and radiation) will be set up to help selecting the flame arrester and designing new flame arresters for new conditions. The research contents are as follows: (1) A complete mechanism of flame quenching in micro-channels is established and a solid theoretical foundation is laid for establishing the accurate mathematical model; (2) On the basis of the mechanism built for the combustion, the accurate mathematical model is set up. In addition, novel flame arresters will be designed and predicted with the integrated models; (3) New crimped ribbon flame arresters is designed based on the design concepts summarized by us. Finally, new flame arresters are tested and verified experimentally. Since the applicant has rich experiences in the flame quenching mechanism and design of flame arresters, this project is very promising. This project can solve the difficult problems in the design and selection of flame arresters in the industry, and it will make a big contribution to safe production in China.

波纹板阻火器可用于超音速防爆、抑爆，对于化工安全生产至关重要。迄今为止，阻火器的设计主要依靠先经验后实验的方法，盲目性大、安全性低，花费高且周期长。数值模拟方法具有经济、快速的特点，然而其可靠性、精准度依赖于数学模型。因此，本项目力求建立包含高温流体流动、剧烈燃烧反应、传热（包括热对流、传导及辐射）的精准数学模型，并以此为基础进行新工况下阻火器的选型以及新型阻火器的设计。具体研究内容包括三个方面：（1）建立火焰在微通道内淬熄的完整机理，为数学模型的建立打下理论基础；（2）基于建立的机理，建立精准的数学模型，设计结构优化的阻火器并进行数值模拟验证；（3）依据设计原理制造新型阻火器，并进行实验测试和验证。项目申请人在火焰淬熄原理和阻火器研发方面具有丰富经验，如成功，将一举解决特殊用途阻火器选型和设计的难题，为我国安全生产做出贡献。

波纹板阻火器是一种重要的化工安全装置，采用数值模拟的方法对其进行合理设计具有广阔的前景。数学模拟方法的可靠性和准确性依赖于建立的数学模型。本研究建立了波纹板阻火器微通道的集成数学模型，探讨了微通道内火焰传播流体流动的流型及4个化学反应动力学机理对阻火器阻火性能预测精度的影响。在确定流型的基础上，为数值模拟阻火器建立了新的火焰淬熄判断标准。研究结果表明，阻火器微通道的反应流动是湍动流动；由于反应动力学模型Mansouri et al. (2016)在阻火速度下，预测的出口温度与丙烷的自燃点吻合最好，故该模型是四个常见丙烷燃烧模型中最精确的，也完全满足工程设计的需要。获得了微通道内各组分质量分数分布、温度场分布等这些在实验中因通道尺寸过小而无法测量的数据，深化了对微通道内化学反应流动和传热的了解。在此数学模型基础上，本项目提出两种新型板式阻火器结构，一种是微通道呈波浪型，另一种是微通道周期性缩扩型。此外，考虑到火焰结构与形态对其能否在阻火器内淬熄有较大影响，所以本项目搭建了实验装置，研究了丙烷与空气非预混气体的燃空当量比、非预混气速度、烧嘴的放置角度对火焰结构与形态的影响，揭示了一个新现象：烧嘴的放置角度对火焰形态有影响。当烧嘴水平放置时，随燃空当量比的增大，火焰向上弯曲；而同等情况下，当烧嘴竖直放置时，火焰没有向上弯曲现象，仅呈现轻微左右不对称。本项目建立的集成数学模型是一个可靠的工具，可用于丙烷专用波纹板阻火器的优化、设计及选型。本项目所开展的火焰结构与形态基础研究，对研究微通道内火焰传播提供了基础数据，具有重要意义。