Impacts of ignition position on secondary explosion outside vessels

doi:10.16265/j.cnki.issn1003-3033.2021.09.013

Abstract

Abstract: In order to prevent external explosion induced by methane explosion venting, numerical simulation of explosion venting process was carried out by using Simtec software for different ignition positions, including front ignition, central ignition and rear ignition. Then, phenomena of secondary explosion were observed and simulation data were analyzed. The results show that better "pressure relief" effect can be achieved by setting the rupture disc, but explosion venting induces secondary explosion outside vessels, which needs to be focused on and prevented. Pressure of measuring points inside containers will approach to peak value when the second peak value caused by secondary explosion occurs at point 6 in explosion vent hole. Ignition position directly affects amount of unburned methane released during explosion venting, and thus impacts secondary explosion intensity. As a result, secondary explosion comes as the strongest for the case with rear ignition, followed by central ignition and front ignition which is the weakest one. The closer it is to explosion vent, the weaker external secondary explosion intensity will be. Therefore, explosion vent should be located close to the areas prone to have an ignition source.

Key words: ignition position, outside of vessel, secondary explosion, explosion venting, peak pressure

CLC Number:

X932

MA Qiuju, SHAO Juncheng, WAN Mengsai, WANG Legeng, Wang Wei. Impacts of ignition position on secondary explosion outside vessels[J]. China Safety Science Journal, 2021, 31(9): 90-98.

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