Fundamentals of Combustion Safety Scenarios for Hydrogen

Introduction

Hydrogen is a powerful energy vector, but its deployment at the scale considered today by governments and companies cannot be achieved if safety associated with combustion hazards is not mastered and regulated. Hydrogen leaks occur and lead to fires and explosions, which must be prevented.

Need for Regulations

To do this, regulations are needed, but these regulations are based today on an incomplete understanding of the fundamental mechanisms controlling the combustion of hydrogen in air or have to consider new usages of hydrogen such as transportation (aircraft, trains, cars…).

Project Overview

SAFE-H2 combines theory, high-precision experiments, and simulations to provide reliable knowledge on the ignition, propagation, acceleration, and mitigation of hydrogen-air flames in three canonical cases:

1. Flames stabilized on a hole
2. Flames interacting with a wall
3. Explosions in closed vessels

Collaboration

The proposal gathers:

1. IMFT: Two experimental sites dedicated to hydrogen will be used for low (<40 kW) and high power (300 kW) experiments.
2. CERFACS: Provides the High-Performance 3D simulation tools used to compute all IMFT experiments.

Experimental Diagnostics

Experimental diagnostics coming from the aerospace field will be applied to safety scenarios at IMFT to validate simulation tools. SAFE-H2 will focus on generic, simple cases to tackle the fundamentals of hydrogen-air flames so that simulation tools incorporate correct, validated physical models and can replace costly and dangerous experimental tests.

Validation Process

All SAFE-H2 experiments will be designed to be used for simulation validations. These detailed comparisons between simulation and experiment will be used to test models for:

1. Hydrogen-air chemistry in the gas phase and near walls
2. Autoignition and plate ignition
3. Flame-turbulence and flame-wall interaction
4. Transition to detonation

Expected Outcomes

SAFE-H2 will deliver fundamental science but also models for all simulation codes used in industry and regulatory agencies to understand and regulate combustion safety for hydrogen.