在石英灯辐射下研究化石英陶表面的热分布特征
Hao Chen1, Wei Li1, Shimin Zhu1
1The State Key Laboratory of Environment-Friendly Energy Materials, School of Materials and Chemistry, School of Information Engineering, School of Mathematics and Science, Southwest University of Science and Technology, Mianyang 621010, China.
Micromachines
|June 28, 2023
概括
研究人员在高温下研究了化石英陶中的热传递. 纤维结构显著影响隔热,沿杆纤维传热速度较慢,这对于飞机的热管理至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 航空航天工程 航空航天工程
- 热力工程是热力工程中的一个.
背景情况:
- 在航空材料中,高温热传递至关重要.
- 化石英陶是具有潜在航空航天应用的先进材料.
- 了解它们在极端条件下的热性能是必不可少的.
研究的目的:
- 为了研究高温下化石英陶材料的传热性能.
- 分析表面热流对内部温度场的影响.
- 为高速飞机的隔热设计提供理论指导.
主要方法:
- 使用石英灯 (45-150千瓦加热功率) 对化石英陶样品进行实验性辐射.
- 测量样品表面温度和热流分布.
- 有限元法 (FEM) 分析用于研究传热特性和温度场.
主要成果:
- 纤维骨架结构显著影响隔热;沿杆纤维的纵向传热速度较慢.
- 表面温度分布随着时间的推移而稳定,达到平衡状态.
- 增加的辐射热流导致更高的表面温度 (在5kW输入功率下高达1153°C),但也增加了温度不均性 (不确定性高达12.28%).
结论:
- 纤维增强的化石英陶具有异型热传递特性.
- 材料的绝热性能在很大程度上取决于其结构特征和应用的热流量.
- 这些发现为设计在极端温度下运行的先进飞机的热保护系统提供了宝贵的见解.
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