Vortex-induced vibration represents a critical mechanism of structural damage,which not only reduced service life of workpieces but can also lead to structural deformation and failure,thereby posing safety risks or causing economic losses. This study conducts a numerical simulation of vortex-induced vibrations in porous media cylinders using CFD software, employing the k-ω turbulence model and SIMPLE pressure-velocity coupling method.Simulations were carried out on single porous media cylinders, three porous media cylinders,and transversely arranged cylinders in matrix configurations to study vortex-induced vibration problems under various scenarios.By comparative analysis,the study examined the impact of porous media on cylinder vortex-induced vibrations in different arrangement scenarios.The results indicate that in all arrangement scenarios, the addition of porous media can result in uniform force distribution on the cylinders and a more stable flow field,effectively eliminating the occurrence of vortex-induced vibrations.This extends the service life of the workpieces,enhances efficiency,and demonstrates significant practical value and application prospects.

To enhance the flowability of waxy crude oil, seven paraffin?degrading strains were screened using paraffin as the sole carbon source. Their paraffin removal efficiency, emulsification capability, and hydrophobicity were evaluated to identify high?efficiency degraders. Strains with optimal growth characteristics were selected based on growth curves, and microbial consortia were constructed through optimized combinations. Cultivation conditions were further refined using single?factor experiments and response surface methodology (RSM). The orthogonal experimental results indicate that when constructing the compound microbial consortium with Broussonetia papyrifera, the inoculation amounts (volume fractions) of strains H1, H3, and H4 should be 1.0%, 2.0%, and 0.5% respectively, respectively, the paraffin removal rate of the consortium reached 58.7%. The optimized cultivation conditions were determined as follows: temperature at 41.8 ℃, inoculation volume at 3.0%, and shaking speed at 181

r/min. The influence of factors on paraffin removal followed the order: cultivation temperature > inoculation volume > shaking speed. After optimization, the paraffin removal rate of the consortium increased to 62.1%. When the microbial consortium was applied to treat waxy crude oil, the viscosity reduction rate reached 51.5%, significantly improving the fluidity of the crude oil and thereby enhancing pipeline transportation efficiency.