在复杂的液体介质中全面研究非静止热传递的实验设置
1Institute of Thermal Physics, Ural Branch, Russian Academy of Sciences, Amundsena St. 107a, Ekaterinburg 620016, Russian Federation.
The Review of scientific instruments
|October 17, 2024
概括
这项研究引入了一种用于液体中精确,高速热交换测量的新设置. 它揭示了乙醇与聚乙烯甘醇溶液的不同沸行为,展示了系统区分复杂热力学的能力.
科学领域:
- 热力学是一种热力学.
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
背景情况:
- 研究液体中的非静态热交换需要对小规模热事件进行精确的控制.
- 高热流密度和快速时间尺度带来了重大的实验挑战.
研究的目的:
- 开发和验证用于研究液体介质中的非静态热交换在小尺度和高热流密度的设置.
- 使用同步的电气和视觉数据采集,将热负荷与流体力学相关联.
主要方法:
- 使用线探头 (直径20微米,长0.51厘米) 与高速精密功率控制器.
- 实现的加热时间从1到300毫秒,热流密度从1到20 MW/m2.
- 同步的恒温仪电信号采集与高速视频录制.
主要成果:
- 在可重复的实验中,证明了热释放的精确控制 (准确率为0.05%).
- 观察并比较了乙醇和水溶液中的30%体积的聚乙烯甘醇-425之间的明显沸模式.
- 测试物质之间在加热和沸过程中发现了质量差异.
结论:
- 开发的设置准确地捕捉了液体中的非静态热交换现象.
- 该系统有效地区分了简单物质和具有独特相位过渡特性的溶液之间的热流体行为.
- 这种方法提供了一个强大的工具,用于研究微小规模的复杂热力学.
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