| 摘要: |
| 为了找到一种非接触式的降低真空冷却失重率的方法，本文首先借助高速相机研究了圆管内水的失重机理。然后，在此基础上研究了不同降压方案对不同管径（直径分别为27 mm，22 mm和12 mm）内水的失重率的影响。结果发现: 1)水的失重主要是汽弹对液态水的弹射作用引起; 2)在闪点附近适当地降低真空泵抽速可以显著地降低失重率（降幅可达到72%); 3）在闪点附近降低抽速时，圆管的直径越小，水的失重越大。 |
| 关键词: 真空冷却 失水率 抽速 管径 |
| DOI： |
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| 基金项目:国家科技支撑计划（2013BAD19B00）资助项目。 |
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| Effect of Bubble Development on the Weight Loss Rate of Water during the Vacuum Cooling Process |
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Song Xiaoyan, Liu Baolin
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| (Institute of Cryobiology and Food Freezing, University of Shanghai for Science and Technology) |
| Abstract: |
| To find a non-contact method that can reduce the weight loss of food during the vacuum cooling process, the mechanism of the water losing in tuber was studied firstly with the help of a high speed camera. Then, the effect of different depressurization schemes on the water loss in different tubers (with diameters of 27 mm，22 mm and 12 mm respectively) was studied based on the above conclusion. The results show that: 1) most of the lost water is launched out by the taylor bubble in the tube; 2) slowing the vacuum speed suitably while the total pressure is close to the flash point can reduce the weight loss significantly (the decreasing ratio was 72%); 3) using the tube with a smaller diameter can caused a higher weight loss when the pressure is close to the flash. |
| Key words: vacuum cooling weight loss pump speed tube diameter |
