Additive manufacturing of porous structures for combustion of methane-air mixtures

Abstract

This thesis focuses on the design, additive manufacturing, and experimental testing of ceramic Kelvin cell porous structures for the combustion of lean methane-air mixtures. The primary objective was to develop functional burner prototypes with defined geometries and determine their stability limits. The manufacturing phase utilized accessible Masked Stereolithography (MSLA) technology combined with the commercial ceramic composite Porcelite. The process was optimized by establishing precise printing parameters and modifying the thermal sintering cycle, achieving high geometric fidelity and structural integrity of the ceramic components. The experimental section focused on establishing stable operability maps for three lattice variants with different pore diameters (Dp = 1.7 mm, 2.3 mm, and 3.4 mm). The results demonstrate that pore diameter significantly influences flame stability. The structure with a 2.3 mm pore diameter was identified as the most effective, offering a 33.3% wider stability range compared to the smallest variant and sustaining stable combustion down to an equivalence ratio of φ = 0.5. This work confirms that accessible additive manufacturing provides an effective route for developing advanced porous burners and establishes a foundation for future research into ultra-lean combustion regimes.