小尺寸聚甲基丙烯酸甲酯燃烧速率分布研究

摘要

The mass burning rates of small scale polymethyl methac?rylate (PMMA) in vertical and horizontal orientations were investi?gated both theoretically and experimentally. By analyzing the ener?gy balance on the burning surface and building the simplified model of convective heat flux and radiation heat flux from the flame to the fuel, the mass burning rate was calculated, which exhibited a good agreement with the result obtained by measuring the surface regres?sion rate. The results shows that, the mass burning rate follows a power law decay along the center line for the combustion in vertical orientation. For the combustion in horizontal orientation, the mass burning rate exhibits a linear decay along the center line from the side to the center of the PMMA;however, in the area near the cen?ter the mass burning rate was constant.%对垂直和水平方向的小尺寸聚甲基丙烯酸甲酯(PMMA)燃烧速率进行了理论分析和实验研究.通过分析燃烧体表面能量守恒、建立火焰对燃烧体表面的对流和辐射热反馈简化模型得出PMMA理论燃烧速率,并利用实验测定燃烧界面的后退速度得出样品的实际燃烧速率,对比两者得出的结果发现吻合较好.实验结果表明,垂直方向PMMA的燃烧速率沿中心线向上呈幂函数衰减;水平方向PMMA的燃烧速率沿中心线由边缘至中心呈线性衰减,但在靠近中心区域的燃烧速率不变.