Field Test Series for Development of Mitigation Barriers and its Designs Against Hydrogen Explosion

A field test series where a composite pressure vessel for hydrogen is exploded by fire 1) to provide the facts and the data for the safety distance based on overpressure; 2) to validate the current status of mitigation barrier per KGS FP216 and further designs for developments of the codes and standards relating to hydrogen refueling stations. A pair of barriers to be tested are installed approximately 4 m apart, standing face to face. The explosion source is a type-4 composite vessel of 175 L filled with compressed hydrogen up to 70 MPa. The vessel is in the middle of the barriers and the body part is heated with an LPG burner until it blows out. The incident overpressures from the blast are measured with 40 high-speed pressure sensors, which are respectively installed 2 to 32 m away from the explosion. In the tests with the barrier constructed per the current status of KGS FP216, the explosion of the vessel resulted in partial destruction of the reinforced concrete barrier and made the steel plate barrier dissociated from the foundation then flew away approximately 25 m. The peak overpressure was 14.65 kPa at 32 m. The test data will be further analyzed to select the barriers for the subsequent tests and to develop the codes and standards for hydrogen refueling stations.