Hydrogen combustion in a flat semi-confined layer with respect to the Fukushima Daiichi accident

- Critical conditions for flame propagation regimes in a layer geometry are analyzed.
- Numerical simulation of hydrogen explosion reproduces real strength of shock waves.
- From 80 to 200 kg of hydrogen were exploded during Fukushima (Unit I) accident.
- A sonic deflagration with TNT equivalent of 800 kg was the most probable regime.