| 摘要: |
| 过冷水法动态冰浆制取技术是一种有望实现大规模应用的动态制冰方法，工业上常用施加超声场的方式解除过冷水的过冷态并生成冰浆。本文实验研究了不同超声场对质量分数为3%的氯化钠溶液结晶过冷特性、生成冰晶尺寸及粒径分布的影响。结果表明：一定功率和频率的超声场的引入可快速解除过冷，使溶液在接近超声辐照温度下成核，且高功率、低频率的超声场更有利于成核发生。当功率、频率、辐照温度分别在10.0~40.0 W、28~40 kHz及0~4.0 ℃范围内，最佳超声场设置方案为超声功率40.0 W、频率28 kHz、辐照温度2.0 ℃；超声场的施加可显著减小冰晶尺寸；随着成核后超声辐照时间的延长，冰晶粒径先增大后趋于平缓，超声功率及频率的变化对冰晶粒径尺寸的影响无显著作用。 |
| 关键词: 过冷度 粒径 超声场 冰浆 过冷溶液 |
| DOI： |
| 投稿时间：2021-02-14 修订日期：2021-05-06
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| 基金项目:国家自然科学基金（22008034），福建省自然科学基金(2020J01518)和福州大学国家环境光催化工程技术研究中心开放课题(NERCEP-201903)。 |
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| Effect of Ultrasonic Field on Crystallization of Supercooling Aqueous Solution |
| Liu Xi,Li Yueling,Wang Jinhui,Lin Li,Li Xuelai |
| (College of Chemical Engineering, Fuzhou University;Research Institute of Photocatalysis, Fuzhou University) |
| Abstract: |
| Dynamic ice-making technology using supercooling water is expected to realize large-scale applications. In industry, the ultrasonic field is often used to release the supercooling state of supercooling water and generate ice slurry. In this study, the effect of different ultrasonic fields on the supercooling characteristics of crystallization, the size of the ice crystals, and the particle size distribution of ice crystals of 3% sodium chloride solution, were studied experimentally. The results showed that the introduction of an ultrasonic field of a certain power and frequency can quickly release the supercooling state. It was also found that the solution nucleation temperature was close to the ultrasonic irradiation temperature, and the ultrasonic field with high power and low frequency was more conducive to nucleation. The power, frequency and irradiation temperature were varied from 10.0 W to 40.0 W, 28 kHz to 40 kHz, and 0 ℃ to 4 ℃, respectively. The optimal ultrasonic field scheme was set as the power at 40.0 W, the frequency 28 kHz, and the irradiation temperature 2.0 ℃. An ultrasonic field can significantly reduce the crystal size. With the extension of the ultrasonic irradiation time after nucleation, the size of the ice crystals first increased and then leveled off. The changes in ultrasonic power and frequency had no obvious effect on the size of the ice crystals. |
| Key words: degree of supercooling particle size ultrasonic field ice slurry supercooling solution |
