Leakage Hazard Analysis of Hydrogen Blended Natural Gas Station Field Based on PHAST

To investigate study the leakage and diffusion characteristics of hydrogen-blended natural gas in station fields, simulation calculations and safety analyses of combustible gas diffusion, fire, and explosion for different leakage scenarios were conducted using PHAST software by DNV., A risk map for personnel in the station field was then generated. The results indicate that large-hole leaks primarily spread near the surface, while small-hole leaks rapidly disperse to higher altitudes due to factors such as flow rate, wind speed, and gravity. In the event of a jet fire, the thermal radiation at the fire's center quickly rises to its maximum value, stabilizes, and then gradually decreases to its minimum. When an explosion occurs, the affected area expands significantly with an increase in hole diameter. These findings provide guidance for equipment and pipeline placement, hazardous area zoning, and emergency response procedures following station reconstruction.