防火堤半径对液氢泄漏危险性的影响OA

Dikes are effective measures to limit the consequences caused by liquid hydrogen tank leakage.Combining the simplified pool model with the two-phase multi-species model,numerical simulations of the NASA-6 experiment were conducted.By controlling the maximum liquid pool radius in the simplified pool model,the restricting effects of dikes on liquid pool spreading and evaporation were considered,enabling a systematic analysis of dike radius influences on hazard regions.Results indicated that dikes effectively constrained high-concentration hydrogen dispersion ranges and reduced the extent of cryogenic damage to hydrogen sensors,thereby facilitating timely leakage detection.However,an excessively reduced dike radius(i.e.,1.5m)may conversely elevate risks in localized downwind near-ground areas(1m height),necessitating a 20%extension of sensor deployment coverage.In addition,under identical leakage and environmental conditions,the dike radius positively correlated with both the stabilization time and dissipation duration of flammable clouds.Linear relationships existed between dike radius and both the maximum downwind dispersion distance and maximum height of flammable clouds,while a quadratic function governed the maximum volume of flammable clouds with respect to dike radius.These findings provide valuable guidelines for dike design.