The study of horizontal extension distances for inclined ethylene buoyant jet fires

As one of the most important raw materials in petrochemical industry, ethylene is widely used in the production of polyethylene, vinyl chloride and so on. Experiments were conducted on inclined ethylene jet fires to study the flame horizontal extension distance. Two nozzles with inner di-ameters of 6 mm and 10 mm were chosen in current study. Four different upward inclined angles of 0 degrees, 30 degrees, 60 degrees and 90 degrees relative to the horizontal direction were employed. The horizontal exten-sion distances of ethlene jet fires increase with increasing heat release rate. For a fixed heat release rate, the horizontal extension distance decreases when the inclined angles increase. Similarity analysis was accomplished, and the result demonstrates that the dimensionless hori-zontal extension distance (Lph/d) can be correlated to the flame Froude number (Frf). By fitting the experimental data, the relationship between the dimensionless horizontal extension distance and the modified flame Froude number Frf*(Frf* = cos theta 3/4. Frf) was derived, and the correlation can well predict the data in current work as well as these from previous studies. For vertically ori-ented ethylene jet flame (theta=0 degrees), the normalized flame width (W/d) was exponentially correlated to the flame Froude number by a power of 0.41.