旋转爆轰三维胞格形成机理与数字化模拟研究

As the fundamental of gaseous detonation mechanism, cellular structure not only characterizes gaseous detonation kinetics, but also is an essential content in the field of accident development analysis. However, current research of cellular structure is far from being understood quantitatively. Furthermore, the development and predict theories of the three-dimensional cellular structure remains a formidable task. All these important research questions cannot be avoided in detonation mechanism research..In order to solve above scientific questions, methods combination of detonation experiments in multiple structure tubes, digital programming calculation, and numerical calculation are defined to investigate quantitative kinetic parameters and explore three-dimensional cellular structure and formation mechanism. Firstly, circumferential and transversely triple point trajectory patterns are analyzed from records on side wall smoked foils and end-on smoked glassed which are obtained from detonation experiments in different initial pressure of multiple in three type’s tubes premixed mixtures. Velocity records are gathered to confirm detonation experiment succeed in different boundary conditions. Secondly, a discrete program is prepared for pattern records from smoked foils and end-on glasses to assemble cellular structure digitized data. And then cellular structure kinetic parameters are calculated as selected standards of premixed mixtures. Meanwhile, HD flash camera is used to observe longitudinally and transversely detonation propagation phenomena in transparent tube segment and end surface. Tracking technology experiments and scanning electron microscopy are adopted to study the smoke traces erasing mode to study the precise mechanism by which the soot is removed by the passage of the triple point over the soot-coated surface. Finally, three-dimensional cellular structure and its statistical data base are fund established through digitalized image processing program for side wall and end surface cellular pattern. Numerical model of three-dimensional cellular structure of instability detonation based on adhesive tape chemical reaction equation is built and improved after comparison with digital database. The three-dimensional cellular structure prediction and mechanism is ultimately theoretical developed.

作为气相爆轰机理的基础，胞格结构表征爆轰动力学特征，在安全领域更是研究事故发生、发展的关键，但其研究距定量分析甚远。同时，建立三维胞格结构及预测理论仍然艰巨，是研究爆轰机理的重要问题。.为解决以上问题，通过多组管道实验、编程计算和数值建模计算相结合的研究方法，探讨胞格结构定量动力学参数与三维胞格结构及形成机理。通过三类管道内爆轰实验，得到侧壁烟膜及端面烟熏玻璃的记录及爆轰速度，给出不同预混气在不同初始压力下的壁面、端面胞格。编制程序将记录离散化，获取胞格结构的数字化数据，计算胞格结构动力学参数，作为选取预混气的标准。同时，利用高清摄像，观察透明管段及端面的传播现象；利用追踪技术和电镜扫描研究烟膜擦除模式，给出留迹机制。侧壁和端面胞格数字化后，获得三维胞格结构及统计数据。建立基于粘带化学反应方程三维不稳定爆轰的数值计算模型，与数据库对比调试，发展预测三维胞格结构的理论，得到形成三维胞格的机理

爆轰胞格结构一直是研究人员关注的重点，边界条件、气体性质等对胞格结构影响不可忽略。本项目针对多种预混气进行了爆轰实验，采用烟膜记录了侧壁与端面结构.并利用数字图像处理技术处理结果，从爆轰不稳定性角度出发，采用自相关函数等分析方式，对爆轰波胞格结构进行了系统的研究，并对各气体不稳定性进行定量描述。结果表明，轨迹间距数据的柱状图、标准差曲线与自相关函数。数字化处理烟膜图像的技术方法，可减少人为误差，提高数据准确性与说服力。多项式Iα=8.53×10^-4×α^2-0.28α+31.83可用于描述氩气稀释对预混气稳定性的影响。由2H2+O2+3Ar的实验结果可知，氢键的存在可使烟膜结果更清晰，且烃类含有碳原子会对烟膜结果造成影响；另外，管壁对爆轰波的影响可由端面结构描述。本项目给出了胞格结构的新研究方式，对于爆轰机理的研究有重要的意义。