干冰升华:一种计算研究,对几何学效应进行实验验证
Ferruh Erdogdu1, Kimberly Hafner2, Ozan Altin3
1Department of Food Engineering, Ankara University, Ankara, Turkey.
Journal of food science
|January 20, 2025
概括
干冰的升温率取决于几何形状,而不仅仅是质量. 球形形状比块更慢地升华,改善温度敏感产品的冷链物流.
科学领域:
- 物理科学 物理科学
- 化学工程是化学工程的重要组成部分.
- 热力学是一种热力学.
背景情况:
- 干冰对于温度敏感产品的冷链分销至关重要.
- 目前的升华估计 (每天3%-8%) 是一般的,不考虑几何.
- 质量是主要的规格,忽视了对升华率的几何影响.
研究的目的:
- 开发和验证干冰升华的计算模型.
- 为了研究几何和方向对干冰升高率的影响.
- 为了提高对干冰冷却用于实际冷链应用的理解.
主要方法:
- 干冰块的实验性升华.
- 开发和验证一个多物理计算模型.
- 包括辐射和对流传热传输,以及计算流体动力学.
- 在升华过程中对几何特征变化的评估.
主要成果:
- 体积与表面积的比率是潜化冷却性能的一个关键参数.
- 对于相同的质量,球形干冰 (高体积与表面积比率) 的升级速度比块状干冰 (较低比率) 慢近50%.
- 模型验证证实了几何学对升华的显著影响.
结论:
- 干冰的几何形状极大地影响了升温率和冷却效率.
- 优化干冰的形状可以显著改善冷链管理.
- 经过验证的模型为预测和管理干冰升温提供了一个工具.
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