直线运动下移动火源扩散火焰的分形结构特征

Fractal structure characteristic of the diffusion flame of moving fire on linear motion

由高速摄像仪获得移动火源在匀加速直线运动下的火焰图像序列,利用图像处理技术和分形理论,研究其分形结构特征.结果表明:处于匀加速直线运动状态下的移动火源扩散火焰具有分形维数特征,同一加速度下的分形维数随速度增大而增加,当移动火源运动速度达到一定值以后,火焰的分形维数增大的幅度变缓慢;加速度较大的移动火源扩散火焰的分形维数随火源运动速度上升的趋势较快,影响火焰锋面的褶皱和扭曲;移动火源与静止火源有一定的区别,可通过对比两者火焰的分形维数特征来加以识别.

Image series of a moving fire on linear motion were acquired by a high-speed video camera. Applying image processing technology and the fractal theory, the fractal structure characteristic of the diffusion flame of moving fires was studied. The results revealed that the diffusion flame of moving fires possesses fractal dimension characteristics and it increases with the velocity in the same acceleration. When the velocity of a moving fire reaches a certain value, the fractal dimension of the diffusion flame increases within a small range; under the condition of a large acceleration and velocity, its fractal dimension increase rapidly with the velocity, and can influence the wrinkle and distortion. There are certain differences between a moving fire and a static fire, which can be identified by comparing the fractal dimensions of them.