超高次冷却 滴滴凝结 热传递在滑动液体状单层植入表面上的热传递
Ting-En Huang1, Yisheng Lu1, Zhaozhuo Wei1
1Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, China.
ACS applied materials & interfaces
|September 19, 2024
概括
带有聚二甲基) 链的滑动液态表面可以在高次冷却温度下实现连续的滴状凝结和快速滴滴流失. 这些耐用表面实现了高的传热系数,克服了传统超材料的局限性.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 热传递热量转移的方法
背景情况:
- 快速滴滴流出对于热管理和水收集至关重要.
- 超疏水表面在高次冷却温度下面临滴滴固定问题.
- 滑动的类似液体的表面提供增强的稳定性和低粘合力,由于密集,光滑的聚合物链.
研究的目的:
- 开发和描述滑动的液态表面,以实现高效的滴状凝结.
- 为了研究在超高次冷却下滴滴流失行为和传热性能.
- 为了评估这些表面在凝结条件下的长期耐用性.
主要方法:
- 线性聚 ((二甲基) 链对基板的共价结合.
- 使用低温传输电子显微镜对单层形成的表征.
- 在各种次冷却温度下测量凝结热量流和传热系数.
- 使用宏观观观测和环境扫描电子显微镜分析滴滴分布.
主要成果:
- 在超高次冷却温度 (60 K) 实现连续滴状凝结.
- 报告的高冷凝热量流量 (1392.60 kW·m−2) 和传热系数 (23.21 kW·m−2·K−1).
- 经过100小时后,热传递系数仅下降20.3%,证明了出色的耐用性.
结论:
- 滑动的类似液体的表面有效地促进滴滴流失,并在高次冷却下维持滴滴凝结.
- 这些表面解决了热传输性能和耐用性等应用的挑战,如热管理.
- 聚合物链的低摩擦力是防止洪水和提高性能的关键.
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