Thermal radiation from cryogenic hydrogen jet fires

• Published in: International journal of hydrogen energy 2019-04, Vol.44 (17), p.8874-8885
• Main Authors: Cirrone, D.M.C., Makarov, D., Molkov, V.
• Format: Article
• Language: English
• Subjects: CFD; Cryogenic; Hydrogen; Jet fire; Radiative heat transfer
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2018.08.107

The thermal hazards from ignited under-expanded cryogenic releases are not yet fully understood and reliable predictive tools are missing. This study aims at validation of a CFD model to simulate flame length and radiative heat flux for cryogenic hydrogen jet fires. The simulation results are compared against the experimental data by Sandia National Laboratories on cryogenic hydrogen fires from storage with pressure up to 5 bar abs and temperature in the range 48–82 K. The release source is modelled using the Ulster's notional nozzle theory. The problem is considered as steady-state. Three turbulence models were applied, and their performance was compared. The realizable k-ε model showed the best agreement with experimental flame length and radiative heat flux. Therefore, it has been employed in the CFD model along with Eddy Dissipation Concept for combustion and Discrete Ordinates (DO) model for radiation. A parametric study has been conducted to assess the effect of selected numerical and physical parameters on the simulations capability to reproduce experimental data. DO model discretisation is shown to strongly affect simulations, indicating 10 × 10 as minimum number of angular divisions to provide a convergence. The simulations have shown sensitivity to experimental parameters such as humidity and exhaust system volumetric flow rate, highlighting the importance of accurate and extended publication of experimental data to conduct precise numerical studies. The simulations correctly reproduced the radiative heat flux from cryogenic hydrogen jet fire at different locations. •Validation of a CFD model to simulate thermal hazards from cryogenic H2 jet fires.•Realizable k-ε model shows the best agreement with experiments.•10 × 10 is the minimum number of DO angular divisions to provide a convergence.•Simulations show sensitivity to water vapour in air and gases extraction system.•Simulations reproduce experimental radiative heat flux at different locations.