Freezing of water droplet is widely seen and important in the fields of aerospace, cold energy storage, and power production. To investigate the freezing process of a sessile water droplet on a horizontal cold plate, a theoretical model was developed. Different from previously reported models, the effects of supercooling and gravity on the physical properties and the water droplet profile are both considered, respectively. This model is validated with the experimental data of two parameters, including the freezing time and the freezing front radius. The results indicate that the deviation of freezing time is decreased from 7.69% to 0.17%, while the accuracy improved by 7.52%. The average deviation of the freezing front radius is decreased from 142.90 μm to 57.94 μm, with the accuracy improved by 59.46%. At the freezing stage, the appearance of the dynamic growth angle contributes to the less deviation of the freezing front radius. The eccentricity of droplet shape decreases from 0.45 to 0.03, with the eccentricity decreased by 93.45%. The temperature change rates inside a droplet show a gradually decreasing tendency, and the temperatures at different droplet locations present different limiting values. The findings of this study are beneficial for understanding droplet solidification process as well as new technologies for refrigeration, deicing, and defrosting.

水滴的冻结在航空航天、冷能储存和电力生产领域被广泛使用和重要。为了研究水平冷板上固定水滴的冻结过程，开发了一个理论模型。与先前报道的模型不同，分别考虑了过冷和重力对物理性质和水滴轮廓的影响。该模型通过冻结时间和冻结锋半径两个参数的实验数据进行验证。结果表明，冻结时间偏差由7.69%降低到0.17%，精度提高7.52%。冻结锋半径的平均偏差从142.90 μm减小到57.94 μm，精度提高了59.46%。在冻结阶段，动态增长角的出现有助于减少冻结锋半径的偏差。液滴形状的偏心率从0.45降低到0.03，偏心率降低了93.45%。液滴内部的温度变化率呈现逐渐降低的趋势，不同液滴位置的温度呈现不同的极限值。该研究结果有利于理解液滴凝固过程以及制冷、除冰、除霜新技术。并且不同液滴位置的温度呈现不同的极限值。该研究结果有利于理解液滴凝固过程以及制冷、除冰、除霜新技术。并且不同液滴位置的温度呈现不同的极限值。该研究结果有利于理解液滴凝固过程以及制冷、除冰、除霜新技术。