Advancements in combustion technologies: A review of innovations, methodologies, and practical applications

This review comprehensively examines key advancements in combustion technologies, multi-scale modeling approaches, and experimental diagnostics, highlighting their contributions to enhancing energy efficiency, reducing emissions, and advancing sustainable energy solutions. Homogeneous Charge Compression Ignition (HCCI) achieves thermal efficiencies up to 50 %, while Reactivity Controlled Compression Ignition (RCCI) reduces NO_x emissions by up to 90 % and improves brake thermal efficiency by 43 %, demonstrating significant potential for low-emission power generation. Pressure Gain Combustion (PGC) achieves thermodynamic efficiency improvements with pressure ratios reaching 2.0, while Plasma-Assisted Combustion (PAC) shortens ignition delay by 35 %, enabling stable operation under lean conditions. Multi-scale modeling techniques, such as hybrid DNS-LES models, achieve a 5 % error margin in flame speed predictions, and Adaptive Mesh Refinement (AMR) reduces computational costs by 50 % without compromising accuracy. Experimental diagnostics, including Laser-Induced Fluorescence (LIF), Particle Image Velocimetry (PIV), and Tunable Diode Laser Absorption Spectroscopy (TDLAS), deliver high-resolution measurements, with PIV capturing flow fields at over 10 kHz and high-speed imaging recording transient combustion events at up to 100 kHz. Future research directions emphasize advancing low-temperature combustion strategies, integrating Artificial Intelligence (AI)-driven modeling techniques, and developing hybrid diagnostic methods for real-time combustion analysis. These advancements collectively support the transition to cleaner, more efficient combustion systems, contributing to sustainable energy solutions and guiding future innovations in combustion science and technology.