数字模拟和研究热量和质量转移在混合超声波/对流式干燥机中的研究
Kaikang Chen1,2, Mehdi Torki3, Davoud Ghanbarian4
1College of Engineering, China Agricultural University, Beijing, 100089 China.
Journal of food science and technology
|April 2, 2024
概括
空气中的超声波功率在薄荷叶的热空气脱水过程中增强了热量和质量转移. 这项研究开发了一个数学模型来预测水分去除,在高达60°C的温度下发现了改进的转移参数.
科学领域:
- 食品科学与技术 食品科学与技术
- 化学工程是化学工程的重要组成部分.
- 生物物理学的生物物理.
背景情况:
- 热空气脱水是保存薄荷等草药的常见方法.
- 优化热量和质量转移对于高效和有效的干燥至关重要.
- 超声波功率已经显示出增强各种物理过程的潜力.
研究的目的:
- 为了研究空气中的超声波功率在薄荷叶脱水过程中对热量和质量转移的影响.
- 在超声波条件下开发出用于除湿曲线的预测数学模型.
- 量化湿度扩散和转移系数的变化.
主要方法:
- 使用不同超声波功率强度 (0104 kW m−3) 的热空气对薄荷薄荷叶脱水的实验研究.
- 开发一种独特的非平衡数学模型来预测水分去除.
- 测量湿度扩散系数,质量转移系数和传热系数.
主要成果:
- 超声波功率显著增加了热量和质量转移参数.
- 湿度扩散系数从0.601 × 10−4到5.937 × 10−4s−1.1不等.
- 质量转移系数范围从4.693 × 10−4到7.975 × 10−4 m s−1.1. 的范围.
- 传热系数从49.2到78.1W m-2 K-1.1不等.
- 观察到传输参数的增强,最高过程温度为60°C.
结论:
- 空气中的超声波功率有效地改善了在薄荷热空气脱水期间的热量和质量转移.
- 开发的数学模型准确地预测了水分的去除,有助于过程优化.
- 超声波辅助脱水为提高草药产品干燥效率提供了一个有希望的方法.
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