In order to ignite the open flow gas of gas well containing sulfur immediately and reliably

the original open flow device is redesigned according to the conditions of gas wells in SINOPEC Southern Company. A mathematical model for the improved open flow device is proposed based on computational fluid dynamics

and the opening flow and concentration field situations are simulated. Combined with experimental results in situ

the simulation results are optimized

and then the range of ignition position for open flow gas is determined

which provides a theoretical and technical supports for the installation of ignition device.