Homogeneous nucleation and heterogeneous condensation of salt vapors near the wall of superheater or reheater tubes greatly improve the sticky propensity of deposited surfaces or impacting particles and then lead to a fast-growing rate of initial layer. Based on the deposition experiment of mechanically mixed KCl + SiO₂ particles in an entrained flow reactor, a numerical model with considering the salt particle vaporization, salt vapor condensation, and its effect on SiO₂ deposition is proposed for simulating impaction and adhesion behavior of molten and solid particles. The results show that deposits are mainly from the impaction of solid and molten particles and the condensation of salt vapors. The condensation rate of salt vapors in the stagnation zone at the windward side of metal probe is maximal. In comparison with the overall deposition rate, although the amount of salt vapors condensed on the probe surface can be negligible, it significantly affects the deposition rate of SiO₂ particles. The coupled CFD model over a link between particle sticking and salt vapor condensation could well simulate the deposition behavior of mechanically mixed ash particles under rich-salt-vapor atmosphere.

中文翻译：

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夹带流反应器中机械混合灰粒沉积速率的数值研究

靠近过热器或再热器管壁的盐蒸气的均相成核和非均相冷凝大大提高了沉积表面或撞击颗粒的粘性倾向，从而导致初始层的快速生长。基于机械混合KCl + SiO ₂颗粒在气流反应器中的沉积实验，建立了考虑盐颗粒蒸发、盐蒸气冷凝及其对SiO ₂影响的数值模型建议沉积用于模拟熔融和固体颗粒的撞击和粘附行为。结果表明，沉积物主要来自固体和熔融颗粒的撞击以及盐蒸气的凝结。金属探头迎风侧滞留区的盐蒸气凝结率最大。与整体沉积速率相比，虽然凝结在探针表面的盐蒸气量可以忽略不计，但它显着影响了SiO ₂颗粒的沉积速率。粒子粘附和盐蒸气冷凝之间的耦合 CFD 模型可以很好地模拟在富盐蒸气气氛下机械混合灰粒子的沉积行为。