Eduardo Pérez (BSC) — Preferential diffusion and thermal radiation modelling in an industrial furnace fed with hydrogen-methane blends

💡A RES Success Story about hydrogen as a potential green fuel 💡 

📋"Preferential diffusion and thermal radiation modelling in an industrial furnace fed with hydrogen-methane blends" led by Eduardo Pérez from Barcelona Supercomputing Center 

The drastic reduction of greenhouse gas emissions needed to palliate the climate change have raised hydrogen combustion as a potential alternative to traditional fuels. Its advantages are mainly its high specific power, that it can be produced from various sources and that its main combustion product is water vapor. As a counterpart, its low mass density and proneness to flashbacks may require to redesign the combustion chambers, added to the potential production of nitrogen oxides in the combustion process

The metallurgical sector requires special attention to hydrogen benefits since its the largest energy consuming sector in the world, as well as it requires previous tests due to the high-price of 'real' experiments. Turbulent combustion simulations become essential in this scenario but, due to the complexity of those flows, typical assumptions deteriorate the quality of the results because of the high diffusivity of hydrogen in comparison to other species, which causes preferential diffusion.

🖥 Thanks to RES Supercomputer #LaPalma from Instituto de Astrofísica de Canarias (IAC), and within the European project HyInHeat, they modelled hydrogen-methane flames in a lab-scale furnace designed by Department for Industrial Furnaces and Heat Engineering, RWTH Aachen University using Large Eddy Simulations with a fine mesh, allowing to capture both the largest and the smallest turbulence vortices. 

In the simulations, they modified the proportion of methane and hydrogen to reproduce different flames and assess how hydrogen affects the flames' morphology and address the preferential diffusion modelling. They found that accounting preferential diffusion shortens the flame length, which is a key measurement since it affects how fast the 'raw' gases are consumed, and that thermal radiation is a key ingredient to predict nitrogen oxides emissions. The combination of both is a topic currently being studied by Barcelona Supercomputing Center researchers. 

The right images compare the instantaneous temperature fields when including or not preferential diffusion for a mixture of 80% methane-20% hydrogen (left) and 20% methane-80% hydrogen (right) 

📹 In the left image there is a 3D simulation of a 80%methane-20%hydrogen flame, as well as an animated version in the video.