关键词: 粒度分布, 烟道气, 模拟, 蒸发, 水蒸气

Abstract: PDA was used to measure the velocity and diameter distribution of two-fluid spray nozzle. Experimental data of velocity and droplet diameter were applied to simulate the desulfurization waste evaporation in one biomass power plant in Jiangsu. Simulation was focused on the droplet diameter and water vapor volume fraction in flue gas which affected the evaporation progress. Results of PDA experiments showed the diameter of two-fluid spray nozzle under special gas-liquid ratio was less than 100μm. Discrete phase model, stochastic trajectory model, and Rosin-Rammler distribution was used to simulate the distribution of spray around (0-100μm). The simulation showed that with the diameter of droplet getting smaller, the complete evaporation time of droplet became shorter and the steady heat absorption time of droplet got shorter. Furthermore, the bigger particle diameter was, the larger complete evaporation time increment of droplet. In terms of water vapor, with its volume fraction in flue gas getting larger, the speed of evaporation slowed down, and the starting of droplet delayed. In addition, the greater the volume fraction was, the larger Sauter mean diameter at exit, but amplitude of increasing in diameter was reduced.

Key words: particle size distribution, flue gas, simulation, evaporation, water vapor