To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen.

The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. The key phenomena are:

  • Electrostatic charge generation and build up associated with multi-phase releases/ mixtures.
  • Evaluation and characterisation of processes that may lead to mixed H2 and O2
  • Ignition of mixed solid/liquid/gas phase involving H2 and O2.
  • The susceptibility of H2/O2 mixtures to ignition by various means.
  • Flammability characteristics for low temperature. Generally where not of interest to spills in the open (as controls for room temperature are worst case) potential mixtures in containers/ process vessels need this information.
  • Other ignition phenomena (spark, fire, catalytic materials, radiation, “diffusion ignition”…).

Led by HSL

WP/ Exp. Nr.Phenomena/ NameTo be investigatedVariation ofLink to results
E4.1General ignitioninfluence of the adiabatic mixing temperature on the standard ignition parametersConcentration/temp
E4.2Electrostatic ignition in cold jetElectrostatic measurements Auto-ignition mechanism BOS images of the jet H2 concentration profileInitial pressure Initial temperature Nozzle diameter
E4.3Electrostatic ignition in cold plumeElectrostatic measurements Auto-ignition mechanism BOS images of the plumes H2 concentration profile
E4.4Ignition above poolignition position BOS imaging temperature profile in a gasMaterial of the ground Initial temperature
E4.5Condensed phase ignitionComposition, energy and types of ignition sourceProduce under idealised conditions to understand sensitivity and conditions for ignition.
Table contains all ignition experiments of PRESLHY project