Modeling the propane combustion process within a micro-catalytic porous combustor by using the lattice Boltzmann method

• Published in: Journal of thermal analysis and calorimetry 2020-02, Vol.139 (4), p.2659-2677
• Main Authors: Feng, X. B., Xu, H. J.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Catalytic converters; Chemistry; Chemistry and Materials Science; Combustion; Combustion chambers; Computational fluid dynamics; Efficiency; Energy conversion efficiency; Equivalence ratio; Gas temperature; Gases; Heat; Heat loss; Inorganic Chemistry; Material properties; Measurement Science and Instrumentation; Methods; Modelling; Organic chemistry; Physical Chemistry; Polymer Sciences; Porosity; Propane; Thermal conductivity; Thermal diffusivity; Thermal properties; Transport
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-019-08818-0

Understanding the micro-catalytic porous combustion mechanisms is vital importance in improving the energy conversion efficiency of a combustion process. However, the investigation on this issue is still challenging due to the complex multiple physicochemical and thermal coupled transport mechanisms occurring in this process. In this work, a coupled lattice Boltzmann model is developed for modeling propane catalytic combustion process within a micro-catalytic porous combustor, in which the coupled transport mechanisms including multi-component gases flow, mass and heat transfers, as well as the heterogeneous catalytic combustion reaction are fully considered. Then, a systematic analysis regarding operating conditions and pore structure parameters was performed to disclose the micro-catalytic porous combustion mechanisms and dominated factors in determining the conversion efficiency. Results show that the conversion efficiency of propane in the micro-catalytic porous combustor majorly depends on the equivalence ratio, gas temperature and support materials properties. With an increment of the equivalence ratio, the conversion efficiency was improved firstly and then reduced, and an optimal combustion performance can be achieved where the equivalence ratio is equal to the chemical equivalent value. As the gas temperature increases, the conversion efficiency rises tremendously. To achieve a desirable combustion performance, the high gas temperature (> 700 K) should be maintained. Moreover, the support materials change the heat transfer and heat loss of the combustor, and the support materials with a low thermal conductivity or thermal diffusivity can reduce the heat loss and therefore enhance the conversion efficiency.