Dispersion of flammable clouds resulting from large spills of liquid hydrogen

摘要

Preliminary findings of hydrogen vapor cloud dispersion experiments are reported. Basic information was obtained regarding the physical phenomena governing the dispersion of flammable clouds formed as the result of spills of large quantitites of liquid hydrogen. The experiments consisted of ground spills of up to 5.7 cubic meters (1500 gal.) of liquid hydrogen, with spill durations of approximately 35 seconds. Instrumented towers, located downwind of the spill site, gathered data on the temparature, hydrogen concentration, and turbulence levels as the hydrogen vapor cloud drifted downwind. Visual phenomena were recorded by motion picture and still cameras. For rapid spills, thermal and momentum induced turbulences cause the cloud to disperse to safe concentration levels and become positively buoyant long before mixing due to normal atmospheric turbulence becomes a major factor.