Image recognition and tracking of flowing sub-flame in downward fire of building insulation materials : A Method based on image morphology, SVM and db-scan algorithm

The fire of the XPS foams on the building facade is a big threat since their fast burning with melting, dripping and flowing. This work developed an image processing algorithm to track the flowing sub-flame and extract the dynamic flame leading curves. The flame leading edges were extracted with Moore-Neighbor tracing algorithm and the image close operation. The image morphology operation was used to locate the candidate flowing sub-flames, and the true melting sub-flames were identified by SVM and a critical distance to the flame leading edge. The moving trajectory of flowing molten sub-flame was obtained through the db-scan method. The results show a wave-like movement of the flame leading curves. The disturbance to the flame leading curve is more obvious for the bigger dripping at the lower locations. The flowing sub-flames can be well tracked by this image processing method. The results indicate that the size of the flowing sub-flames is close to the lognormal distribution.