蒸汽在PM表面凝结的紊流布朗核聚并理论与数值模拟

Theory of Aggregation Kernel of Turbulence and Brown Synergizing Vapor Condensing on the Surface of PM and Its Numerical Simulation

以增加了蒸汽入口的脱硫塔喷淋空间为研究对象,构建PM相变核聚并反应器,研究了超细颗粒物凝结长大机制与脱除效果。通过建立超细颗粒物相变凝结增长动力学模型,同时引入全范围内超细惯性粒子的紊流聚并和布朗聚并核模型,研究蒸汽相变耦合紊流布朗运动脱除超细颗粒物的作用。进一步利用商业软件Fluent的UDF功能,将超细颗粒物相变凝结增长动力学模型写入颗粒群平衡模型中,探索了超细颗粒物在反应器内的沿程反应机理。结果表明：对比不添加蒸汽的超细颗粒物脱除效果,添加蒸汽可有效增加喷淋空间过饱和度,超细颗粒物在反应器入口的布朗运动和紊流运动较明显,大大提高了超细颗粒物的脱除效率。

For the spray space of desulfurizing tower that added the vapor inlet, a reactor of PM aggregation kernel synergizing vapor condensing was built to investigate the mechanism of ultrafine particle condensation, growth, as well as its removal. To clear the impact of heterogeneous condensation which combined with turbulent Brownian motion, the dynamic model of superfine particle growth by vapor condensation, the aggregation kernel models,as well as the Brown model were introduced in. Furthermore, the on-way mechanism of ultrafine particle was studied by means of written the dynamic model of particle growth to the PBM. The results show that the over saturated degree was increased by vapor addition. Meanwhile, the Brownian motion and turbulent motion of ultrafine particle is significant at the reactor inlet, which could greatly improve the removal efficiency of ultrafine particle.