Abstract: This paper conducted a series of methane jet fire experiments under the action of pipelines and studied the influence of pipelines on jet flame morphological characteristics. The jet flame combustion process was recorded during the experiment and the flame visualization images were processed. The results show that vertical jet flame height increases with the increase of nozzle-pipe spacing, decreases with the larger pipe diameter; while the horizontal extension flame width underneath the pipe shows the contrary variation trends. A prediction model for vertical jet flame height under the action of horizontal pipelines was established based on the flame length model of jet fire, and verified by the previous results.

Key words: jet fire, horizontal circular tube, flame height, flame width, pipe diameter