高效的热声绝缘气凝,通过共振腔工程实现
Yiqian Zhou1,2, Lei Li1, Chong Yang2
1National Engineering Research Center of Electric Vehicles, Beijing Institute of Technology, Beijing 100081, China.
ACS nano
|July 24, 2023
概括
研究人员开发了一种新方法来制造轻量级,灵活的热声隔热 (TAI) 气凝. 这些材料为节能应用提供了出色的吸声和绝热性能.
科学领域:
- 材料科学 材料科学 材料科学
- 声学 声学 在声学方面
- 纳米技术纳米技术
背景情况:
- 轻量级,灵活且不可燃烧的热声隔热 (TAI) 材料对于重量敏感的应用,如汽车和航空航天,至关重要.
- 当前的TAI材料往往缺乏多样化的共振腔,这限制了它们的宽带和高效的声学吸收能力.
研究的目的:
- 开发一种新的方法来制造具有增强声学响应力的高性能TAI气凝.
- 创建具有广泛共振腔大小的材料,用于宽带声音吸收.
主要方法:
- 使用各种纳米纤维和冰颗粒,采用了一层一层的冷造技术.
- 这种方法导致垂直孔径和随机孔径,创建一个细胞网络结构.
- 纳米纤维膜被功能化为超薄的纳米纤维鼓,以增强声学性能.
主要成果:
- 制造的气凝表现出广泛分布的共振腔,范围从0.5到300微米.
- 在广泛的频率范围 (63-6300 Hz) 中,实现了0.65的高降噪系数.
- 该材料表现出优异的绝热性能,其低导热率为0.026 W m-1 K-1.1.
结论:
- 一层一层的冷造方法使得超弹性细胞气凝的自下而上的制造成为可能.
- 这些高性能TAI气凝为节能设备,建筑物和宽带声学吸收提供了巨大的潜力.
- 具有纳米纤维鼓的独特细胞结构提供了高效的声波消散和热绝缘.
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