Modeling Droplet Heat and Mass Transfer during Spray Bar Pressure Control of the Multipurpose Hydrogen Test Bed (MHTB) Tank in Normal Gravity
Modeling Droplet Heat and Mass Transfer during Spray Bar Pressure Control of the Multipurpose Hydrogen Test Bed (MHTB) Tank in Normal Gravity
复制标题
DOI：
10.2514/6.2016-4673
复制
发表时间：
2016-07
期刊：
影响因子：
--
通讯作者：
Olga V. Kartuzova;M. Kassemi
中科院分区：
文献类型：
--
作者：
Olga V. Kartuzova;M. Kassemi
提出了一种用于模拟低温储罐压力控制的CFD模型，并将其应用于1GMHTB喷棒冷却实验。采用欧拉-拉格朗日方法跟踪喷雾液滴，捕捉离散液滴与连续空化相之间的相互作用。将喷雾模型与VOF模型耦合，在空隙中执行粒子跟踪，当粒子到达界面时从空隙中移除粒子，然后将其贡献添加到液体中。提出了一种计算液滴空化传热传质的新模型。在这个模型中，允许液滴升温到与液面蒸汽压相对应的饱和温度，然后它蒸发，同时保持在饱和温度。液滴模型与MHTB喷棒冷却实验结果进行了对比，实验结果分别为50%和90%的水箱填充率。将基于T-sat模型的预测结果与以前发展的基于动力学的液滴传质模型的预测结果进行了比较。对两种模型对储罐压力和温度分布以及液滴运动轨迹和温度的预测进行了详细的检验和比较。最后，根据MHTB喷棒混合实验提供的相应数据，验证了液位压力和局部汽液温度的演化。
A CFD model for simulating pressure control in cryogenic storage tanks through the injection of a subcooled liquid into the ullage is presented and applied to the 1g MHTB spray bar cooling experiments. An Eulerian-Lagrangian approach is utilized to track the spray droplets and capture the interaction between the discrete droplets and the continuous ullage phase. The spray model is coupled with the VOF model by performing particle tracking in the ullage, removing particles from the ullage when they reach the interface, and then adding their contributions to the liquid. A new model for calculating the droplet-ullage heat and mass transfer is developed. In this model, a droplet is allowed to warm up to the saturation temperature corresponding to the ullage vapor pressure, after which it evaporates while remaining at the saturation temperature. The droplet model is validated against the results of the MHTB spray-bar cooling experiments with 50% and 90% tank fill ratios. The predictions of the present T-sat based model are compared with those of a previously developed kinetic-based droplet mass transfer model. The predictions of the two models regarding the evolving tank pressure and temperature distributions, as well as the droplets' trajectories and temperatures, are examined and compared in detail. Finally, the ullage pressure and local vapor and liquid temperature evolutions are validated against the corresponding data provided by the MHTB spray bar mixing experiment.