Large Eddy Simulation of A Dual-Fuel Swirled Spray Burner Operating With Hydrogen

Abstract

Hydrogen is under evaluation as a low-emission fuel candidate for future aviation systems. Despite its environmental advantages, its low volumetric energy density presents substantial engineering challenges, particularly in aircraft design and airport fuel handling infrastructure. As an interim solution, fuel-flexible combustion systems, designed to operate efficiently with both hydrogen and conventional hydrocarbons, offer a viable route toward gradual decarbonization of the aviation sector.

However, the inherent complexity of dual-fuel burners, characterized by multi-regime operation and diverse fuel properties, poses several challenges for their numerical modeling. To address these modeling challenges, high-fidelity Large Eddy Simulation (LES) incorporating finite-rate chemistry is one of the most effective tools for capturing the complex dynamics of reactive flows involving hydrogen or hydrocarbon mixtures. Within this framework, the Dynamic Thickened Flame Model (DTFLES) has shown promise for modeling hydrogen flames. However, its applicability to dual-fuel systems, especially those featuring interactions between hydrogen jets and non-premixed hydrocarbon sprays, remains underexplored and requires further investigation. Building on this foundation, the present study evaluates the performance of the DTFLES in simulating reactive flows within laboratory-scale swirled spray burners operating with hydrogen and hydrocarbon spray injection. To mitigate computational expense while preserving chemical fidelity, an analytically reduced mechanism is developed using the ARCANE reduction tool. The model's capability to capture multi-fuel, multi-phase interactions is assessed through direct comparison with experimental diagnostics, including OH-PLIF imaging and flame temperature measurements.