Progress in CFD numerical study on hydrogen and its blended homogeneous fuels combustion

Hydrogen, as a zero-carbon fuel, is central to energy transition due to its clean combustion, high energy density, and full lifecycle low-carbon potential. However, hydrogen combustion presents challenges including high flame speed, wide flammability limits, safety risks, equipment compatibility issues, and high storage/transport costs. Blending hydrogen with conventional fuels offers a practical pathway for low-carbon transition, balancing emissions reduction with engineering feasibility. Computational fluid dynamics (CFD) enables effective simulation of hydrogen-blended combustion processes including flow distribution, temperature evolution, and pollutant formation, providing cost-effective analysis with comprehensive data. This review summarizes the fundamental combustion characteristics of hydrogen and its homogeneous blends, including ignition delay time, laminar flame speed, and pollutant emissions. Focusing on the CFD simulation framework, this review systematically examines the development and applications of core CFD sub-models, including turbulence models, radiation models, combustion models, reaction kinetics mechanisms, and pollutant formation and conversion models. Subsequently, this work integrates experimental and numerical simulation findings to analyze the research progress and practical applications of hydrogen-blended combustion across various systems, from laboratory-scale burners to commercial power plants. Finally, the impacts of hydrogen blending on combustion performance and pollutant emissions are summarized, effectiveness and limitations of CFD sub-models are evaluated, and future research directions are proposed to address existing gaps, such as insufficient research on unconventional pollutants and the need for high-fidelity computational methods. This review indeed provides theoretical support for advancing hydrogen-blended combustion fundamental research and engineering optimization.