Modelling Hydrogen Deflagration in CFD
Why Hydrogen?
Hydrogen is an attractive alternative fuel as the only product produced from combustion is water.
However, there are several challenges which arise from the use of Hydrogen as a fuel.
Hydrogen can be ignited from energy levels as low as static electricity on clothes so safety is a significant concern.
Therefore, steps must be taken to prevent Hydrogen related accidents.
Why CFD?
Computational Fluid Dynamic (CFD) simulations can be used to predict the behaviour of a fuel during combustion. This information can be incorporated into the design process of creating adequate safety mechanisms for fuel cell and hydrogen technologies.
With the support of Turku University of Applied Sciences and Elomatic, the team aim to model the deflagration (rapid yet subsonic combustion) of hydrogen in semi-open ducts using ANSYS Fluent.
This project builds upon work previously completed by Project SUSANA. This is an EU funded project which aimed to produce a CFD model evaluation protocol for the safe use of hydrogen.
Creating a simulation which accurately described the deflagration of Hydrogen proved to be particularly challenging.
The aim was to create the simulation in ANSYS Fluent 19 R2 as it is a widely used CFD software. Fluent is mainly used for modelling scenarios where there is an initial flow but in this case there is no initial flow. Limited research had been carried out on this topic and so we decided to take on this challenge.
By monitoring the flame velocities along the duct, mach number, temperature, water production and overpressures and then comparing these results to published data we managed to prove our simulation successfully described deflagration of hydrogen.
An animation was produced from this simulation which clearly shows the deflagration reaction through the duct.
