关键词: PM2.5捕集, 降膜阵列, 气液交叉流, 传热传质类比, 捕集效率

Abstract: According to the pseudo-homogeneous fluid performance of aerosol particles, a mass transfer analogy model was proposed for PM2.5 collection on the interface of gas-liquid cross flow. With the mechanism analysis on the particle transport behavior analogized to fluid convective heat transfer, which is mainly affected by the Schmidt number (Sc) and its exponent m, an analogous equation of Sherwood number (Sh) of particle transfer was derived for PM2.5 collection through a staggered falling film array (SFFA), based on a widely used equation of Nusselt number (Nu) of convective heat transfer over the staggered tube bundles. From the analogous equation of Sh, a model for prediction of PM2.5 collection efficiency was deduced with the exponent m as the model parameter. The value of m was obtained to be 0.808 via regression analysis of experimental data of PM2.5 collection efficiencies measured in a SFFA consisting of 20 (line)×90 (row) falling film cylinders with diameter of 3 mm. In the range of Reynolds number from 50 to 650, the deviation between the model prediction of PM2.5 mass transfer Sh and the experimental data is within ±20%.

Key words: PM2.5 collection, falling film array, gas-liquid cross-flow, heat and mass transfer analogy, collection efficiency