Integrated Thermo-Kinetic Characterisation and CFD Simulation of Reactive Coal Particle Combustion in a Standardised Explosion Vessel

Coal dust explosions remain a critical safety hazard in underground coal mines, particularly because the explosibility of coal dust is strongly influenced by its thermo-chemical characteristics and combustion kinetics. However, the use of generic or literature-derived kinetic parameters in numerical models may limit the accurate prediction of explosion behavior for coals with different geological and physicochemical characteristics. Therefore, this study aimed to develop an integrated experimental–numerical approach by incorporating experimentally determined thermo-kinetic parameters into Computational Fluid Dynamics (CFD) simulations of coal dust explosions. Four Indian coal samples representing different degrees of gassiness and fiery/non-fiery seam conditions were investigated. Differential Scanning Calorimetry (DSC) was performed in an air atmosphere over 30–1550°C at heating rates of 10–50°C min−1, and the Coats–Redfern integral method was employed to determine the activation energy and pre-exponential factor for devolatilization+ volatile combustion and char oxidation/combustion. These experimentally derived kinetic parameters, together with the measured particle-size distributions, were subsequently incorporated into CFD simulations of a standardised 20-L explosion vessel using a three-step coal combustion mechanism. The simulated maximum explosion pressure ranged from 6.57 to 7.84 bar, while the deflagration index (Kst) ranged from 58.63 to 140.35 bar·ms−1 categorizing all samples in the weak explosion category (Hazard Communication Guidance for Combustible Dusts 2009). Narsamunda coal exhibited the highest explosion severity, which was associated with its higher volatile matter content, lower activation energies, and lower crossing‑point temperature. Temporal distributions of oxygen (O2), carbon monoxide (CO), and carbon dioxide (CO2) further revealed the progression of combustion and spatial variation in the explosion process. The study demonstrates that integrating experimentally derived kinetic parameters with CFD modeling provides a more coal-specific framework for assessing dust explosion behavior. The developed approach can be applied to the safety assessment and risk-based management of coal dust explosion hazards in Indian underground coal mines, including the evaluation of explosion severity, identification of critical combustion conditions, and development of appropriate prevention and mitigation strategies.