Abstract:

A numerical experiment platform was established according to Fletcher〖DK〗’s classical heterogeneous nucleation theory, and the critical saturation of water vapor nucleation on fine particles was simulated.The simulation results were compared with experiment results from literature.It was found that the simulated critical saturation agreed well with experimentsBased on the above calculation, the free energy of embryo formation, critical embryo radius, nucleation rate, and the critical saturation of water vapor (with and without wetting agent vapor) nucleation on PM2.5 from coal combustion were numerically predicted, combined with the physical and chemical characteristics of PM2.5 from coal combustion as well as the values of contact angle and surface tension tested by experimentsThe results showed that the presence of wetting agent in water vapor could lead to lower free energy of embryo formation and smaller critical embryo radius, and cause the magnitude of nucleation rate to increase dramatically and the critical saturation of water vapor to decrease remarkablyThus, with wetting agent in water vapor, the nucleation and condensation capabilities of water vapor were greatly enhanced, but the effects of the five wetting agents used were different, among them SDS and Silanol w22 were desirable choices.