Pore-scale simulation of hydrocarbon fuel flow and heat transfer in porous media

Reactive coolants have gained increasing research attention in transpiration cooling, motivating further investigation into the coupled interactions of flow, heat transfer, and chemical reactions within porous media. In this paper, three three-dimensional spherical particle packing models, namely, simple cubic (SC), body-centered cubic (BCC), and face-centered cubic (FCC), are used to simulate the flow and heat transfer of hydrocarbon fuel in porous microchannels. The impact of different pore structures on the flow-heat-reaction coupling is investigated. The dependence of pyrolysis reactions on flow field is analyzed, revealing the coupling mechanism between heat and mass transfer processes in chemically reactive flow fields. Results presented herein demonstrate that under the same conditions, the SC structure microchannel exhibits excellent cooling performance. When considering cracking reactions, its maximum solid temperature decreases by 38.4% compared with the BCC structure and by 16.6% compared with the FCC structure. The value of Da in the contraction section of pore channel is considerably smaller relative to that in the expansion section, implying a higher dependence of cracking reaction on the flow field within this region. Radial distribution of Le additionally manifests that central region has a lower value than its adjacent region, suggesting a conspicuous dependence on diffusion mechanisms in the central fluid domain.