Additively Manufactured Lattice Structures Reduce Flashback Risk in Hydrogen Jet Flame Combustors
Researchers tested 3D-printed nozzles with porous lattice structures in hydrogen combustors and found they significantly reduce flame flashback—a dangerous condition where flames travel backward into the fuel supply. The study used laser-based powder bed fusion to create body-centered cubic lattice walls with varying porosities and tested them at Reynolds numbers between 9,000-12,000. The findings suggest additive manufacturing can improve hydrogen combustor safety by using cooling effects from unburnt mixture flowing through porous walls.
A new study published on arXiv examined how additively manufactured nozzles with porous lattice structures affect flashback propensity in hydrogen jet flame burners. Five combustor configurations were tested, with particular focus on mixing duct walls incorporating porous media created via laser powder bed fusion. The researchers varied lattice parameters by volume fraction and strut diameter, conducting experiments with pure hydrogen fuel under atmospheric conditions across different equivalence ratios and Reynolds numbers (9,000-12,000). Using flow field measurements, flame imaging, and spectral proper orthogonal decomposition, the team identified transition mechanisms from stable operation to flashback. Results showed that the coarsest porous wall structure provided significantly improved flashback resistance compared to solid walls, with the primary mitigation mechanism identified as a cooling effect from unburnt mixture flowing through the porous media. The findings demonstrate that lattice structures integrated through additive manufacturing offer a viable strategy for hydrogen flashback mitigation.
What different sources said
- arXiv physicsCenter
Effect of Additively Manufactured Wall Lattice Structures on Flashback Limits in a Hydrogen Jet Flame Combustor
Related
Genetic Drift, Not Selection, Drives Rapid Feather Color Evolution in Island Bird Radiation
A new study of an island bird radiation found that rapid evolution of feather coloration is driven primarily by genetic drift in small populations rather than sexual or ecological selection. The research integrated whole-genome data with detailed plumage measurements across complete species sampling to test whether signaling trait evolution correlates with speciation rates. The findings suggest that neutral demographic processes play a central role in generating phenotypic diversity during island radiations, challenging assumptions about the mechanisms driving rapid evolution.
New AI Model Improves Prediction of Therapeutic Peptide Function from Protein Sequences
Researchers developed a lightweight CNN classifier that predicts whether peptide sequences have therapeutic properties, trained on a database of 54,655 peptides across 48 functional categories. The model uses a novel negative sampling strategy to reduce false positive rates from over 60% in previous approaches to 2.1%. This advancement could accelerate drug discovery by enabling faster computational screening of peptide candidates before expensive experimental testing.
Study Shows Different Metabolic Stress Models Produce Distinct Effects on Human Neuronal Networks
Researchers tested three common in vitro metabolic stress models on human-derived neuronal networks and found each produced different patterns of neuronal activity and cell damage. The models tested were hypoxia alone, oxygen-glucose deprivation (OGD), and hypoxia combined with glutamate exposure. The findings suggest that choice of experimental model significantly affects results and that combining electrophysiological and structural analyses is important for accurately assessing metabolic stress in stroke research.