(109a) Modeling of Underground Hydrogen Pipelines

Hydrogen is a critical component in the production of
cleaner fuels.  Underground pipelines
provide a safe, reliable supply of hydrogen to refineries and the petroleum
industry.  Proper assessment of the risks
associated with underground hydrogen pipelines requires an accurate model of the
jet fire consequence.   This paper will
describe experimental and modeling work undertaken in order to define the
appropriate methodology for utilizing the DNV's PHAST software tool to
represent the hydrogen jet fire. 

Two experiments were conducted to measure the flow and
radiation from an intentionally ignited rupture of a 6 inch diameter, 60 barg
hydrogen pipeline buried 1 meter underground. 
Adjustments to PHAST modeling parameters were required in order to
obtain agreement between the measured and predicted radiation and flame length
values. The modeling assumptions and parameter adjustments required include velocity
modification to account for interaction of the flow out of the two ends of the ruptured
pipe and the subsequent discharge from the crater, specification of the
fraction of heat radiated and specification of the angle of the release.