在密集的简单液体中声音的速度
1Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia.
Physical review. E
|August 1, 2025
概括
一个新的公式准确地预测了接近结温度的密集流体中的声音速度. 这种基于热速度和理想气体热容量比的缩放定律,对各种液体和行星条件进行了验证.
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:
- 流体中的声音速度是各种科学和工程应用中的关键参数.
- 了解相位过渡附近的流体行为,如结,对于准确的预测至关重要.
- 现有的模型可能无法充分捕捉声速与密度流体温度之间的复杂关系.
研究的目的:
- 开发和验证一个新的缩放定律,用于简单的密集流体中的声音速度.
- 为了研究声音速度对结温度的依赖.
- 提供一个实用的工具,用于估计未经探索的系统中的声音速度.
主要方法:
- 该研究提出了一个理论缩放规律,用于相对于特征热速度 (v_T) 的声音速度 (c_s).
- 建议的形式是c_s/v_T γ^(1/2) + α(T_fr/T) ^β,其中γ是理想气体热容量比,T是温度,T_fr是结温度,α,β是参数.
- 该模型使用Lennard-Jones流体模拟进行了测试,并与实体液体 (,,,,,甲) 的实验数据进行了比较.
主要成果:
- 拟议的结温度缩放定律准确地描述了简单密集流体中的声音速度.
- 对于莱纳德-斯流体,参数被发现是 γ=5/3,α≈7,和 β=1/3.3.
- 对,,,和甲的实验数据进行了验证,并对依赖物质的适配参数α和β进行了验证.
- 预测与最近在行星内部条件下对甲的实验测量进行了比较.
结论:
- 开发的声速缩放定律提供了一种简单而实用的方法,用于估计密集流体中的声速.
- 这种工具在实验数据稀缺的条件下特别有用,例如行星内部.
- 这些发现有助于更好地了解接近点的流体热力学.
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