Abstract In a gas-solid fluidized bed, volatile liquid injection results in complex flow behaviors in the spray zone. To characterize the liquid existence forms (droplets and liquid films) and fluidization properties in the volatile spray zone, a mesoscale-theory based volatile spray zone model is developed with the consideration of hydrodynamics, heat transfer, and mass transfer. A new energy-based stability condition is established according to two competition and coordination relationships, consisting of the energy dissipation based on the liquid-solid interface change and suspension and transporting of particles. The modeling results agree well with the experimental bed temperature as well as void fraction data, and show that the variation of liquid existence forms is dependent on the ratio of different energy consumption rates under the stability condition. Moreover, the gas-solid drag coefficient in the volatile spray zone is modified. Simulation results also reasonably describe the bed pressure drop fluctuation and particle velocity distribution.

中文翻译：

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喷液气固流化床挥发喷雾区模型与实验

摘要 在气固流化床中，挥发性液体的注入导致喷射区的复杂流动行为。为了表征挥发性喷雾区中的液体存在形式（液滴和液膜）和流化特性，在考虑流体动力学、传热和传质的情况下，开发了一种基于中尺度理论的挥发性喷雾区模型。根据两种竞争和协调关系建立了一种新的基于能量的稳定条件，包括基于液固界面变化的能量耗散和粒子的悬浮和输运。建模结果与实验床温以及空隙率数据吻合良好，并表明液体存在形式的变化取决于稳定条件下不同能量消耗率的比率。此外，修改了挥发性喷雾区的气固阻力系数。模拟结果还合理地描述了床层压降波动和颗粒速度分布。