CFD Simulation And Structure Optimization Of Foam SiC Structure Packing

Foam silicon carbide ceramic material is a new kind of functional materials withlow density and good thermal stability. Due to its high porosity, high specific area,chemistry stability and good mechanical, electrical, abrasion and corrosion resistance,this material has a wide range of application in chemistry, environmental protection,electronics, medicine and many other fields. A new foam SiC ceramic structuredpacking (FSP) is studied in this paper, which combines the respective characteristicsand advantages of corrugated sheets and foam SiC ceramic material.The concept of representative volume element and the principle of averagevolume element were introduced in this paper.Macro-model and meso-modelsof foamSiC structured packing were formed by ignoring real skeleton structure of foamsheet,and the corrugated sheets were solved as porous media model. The simulation resultsfor single gas phase flow were used for the calculation of pressure drop and itsinfluence factors, and analysis of the internal flow status. The simulations oftwo-phase flow were used for study the flow characteristics of liquid film and theinfluence of corrugate sheet structure parameters. The mathematical method andphysical model were validated by comparing the simulation results and experimentaldata. The results showed that, the foam SiC packing with45°corrugation inclinationangle exhibits higher pressure drop and larger velocity gradient. While the diffusiondistance and diffusion area of45°SiC packing are better than the60°.Both thesetwo packings with different corrugation angle exhibit good diffusion phenomenon.The45°SiC structured packing exhibits good liquid distribution but has highpressure drop value, so pulse structure districts are added in corrugated sheets tooptimizecorrugated packing, aiming at reducing resistance, minimizing pressure dropand achieving multiple pulse movements. The so-called pulse structure is to make useof the change and transition of corrugation angle in one packing element height, andthereby to change the gas flow pattern in channels. The gas phase flow was simulatedin pulse foam SiC structured packing, and the influences of the pulse districtsnumberN, the height of pulse structure H, and the length between pulse districts Lwere further discussed. The results showed that, introducing pulse structure districtsin the45°corrugated sheet could effectively improve the homogeneity of fluid withinpacking, reducing the flow resistance at intersections, minimizing the pressure drop and realizing the structure optimization.Pessure drop value can be reduced effectivelyand flow distribution can be improved by increasing the pulse height H appropriately,distributing pulse districts reasonable,increasing the number of pulse districts. Thuswould provide the basis for optimizing the structure of corrugated packing.