一般适用的基于物理的液体状态方程
J E Proctor1, Kostya Trachenko2
1Materials and Physics Research Group, University of Salford, Manchester M5 4WT, United Kingdom.
概括
研究人员为液体开发了一种新的基于物理的状态方程 (EOS),将宏观性质与微观分子行为联系起来. 这种普遍适用的 (GAP) EOS为了解极端条件下的液体和超临界流体行为提供了重大进步.
科学领域:
- 热力学和统计力学的热力学.
- 凝聚物质物理学 凝聚物质物理学
- 行星科学和地质物理学
背景情况:
- 现有的基于物理的状态方程 (EOS) 对固体和气体是很好的,但由于固有的理论复杂性,对于液体不是.
- 当前的液态EOS模型往往是经验性的,复杂的,并且包含物理上无意义的参数,限制了它们对行星内部和工业过程的预测能力.
- 在理论框架中存在一个基本的空白,用于描述高压和高温条件下的液体行为.
研究的目的:
- 开发一种一般适用的,基于物理的状态方程 (EOS) 液体和超临界流体在类似液体的密度.
- 建立宏观热力学特性 (EOS) 和微观液体动力学 (分子跳跃频率) 之间的直接联系.
- 为流体行为提供一个更准确,更有物理依据的模型,适用于极端环境.
主要方法:
- 开发一种新的普遍适用的 (GAP) 状态方程,明确依赖内部能量.
- 集成分子跳跃频率 (液体放松时间) 作为一个关键的微观输入来确定内部能量.
- 通过各种测试方法对实验数据进行验证,包括同位体研究,并与固体和气体EOS模型进行比较.
主要成果:
- 开发的GAP EOS与液体和超临界流体的可用实验数据有很好的一致性.
- GAP EOS成功地将宏观压力-体积-温度 (PVT) 属性与微观液体放松时间联系起来.
- 该模型显示了与凝结相中的固体EOS (Mie-Grüneisen) 有相似之处,但与气体EOS相比存在根本差异.
结论:
- 新的普遍适用 (GAP) EOS为描述液体行为提供了一个强大的基于物理的框架,克服了以前模型的局限性.
- 包含静态能量的半经验术语和格鲁尼森参数是必要的组成部分,类似于固态物理学.
- 进一步的实验数据对于完善和扩展液体EOS模型的适用性至关重要.
相关概念视频
Equation of State
1.7K
The equation of state is an equation that relates physical quantities, such as pressure, volume, temperature, and the number of moles, of a thermodynamics system with each other. The equation relating physical quantities with each other can be a simple mathematical expression or too complicated to express in mathematical form. In either case, a relationship between physical quantities exists. If the equation of state cannot be expressed in a mathematical form, then experimental data and...
1.7K
Clausius-Clapeyron Equation
56.5K
The equilibrium between a liquid and its vapor depends on the temperature of the system; a rise in temperature causes a corresponding rise in the vapor pressure of its liquid. The Clausius-Clapeyron equation gives the quantitative relation between a substance’s vapor pressure (P) and its temperature (T); it predicts the rate at which vapor pressure increases per unit increase in temperature.
56.5K
Van der Waals Equation
4.0K
The ideal gas law is an approximation that works well at high temperatures and low pressures. The van der Waals equation of state (named after the Dutch physicist Johannes van der Waals, 1837−1923) improves it by considering two factors.
First, the attractive forces between molecules, which are stronger at higher densities and reduce the pressure, are considered by adding to the pressure a term equal to the square of the molar density multiplied by a positive coefficient a. Second, the volume...
First, the attractive forces between molecules, which are stronger at higher densities and reduce the pressure, are considered by adding to the pressure a term equal to the square of the molar density multiplied by a positive coefficient a. Second, the volume...
4.0K
Ideal Gas Equation
6.7K
The ideal gas equation is an equation of state that relates the state variables pressure, volume, temperature, and the number of moles of a hypothetical gas. This equation is a combination of four empirical laws, namely Boyle’s Law, Charles’s Law, Avogadro’s Law, and Gay-Lussac’s Law. When the proportionalities of the above four empirical laws are combined, it results in a single proportionality constant known as the universal gas constant.
6.7K
Molecular Comparison of Gases, Liquids, and Solids
40.9K
Particles in a solid are tightly packed together (fixed shape) and often arranged in a regular pattern; in a liquid, they are close together with no regular arrangement (no fixed shape); in a gas, they are far apart with no regular arrangement (no fixed shape). Particles in a solid vibrate about fixed positions (cannot flow) and do not generally move in relation to one another; in a liquid, they move past each other (can flow) but remain in essentially constant contact; in a gas, they move...
40.9K
Energy Conservation and Bernoulli's Equation
8.9K
Applying the conservation of energy principle or the work-energy theorem to an incompressible, inviscid fluid in laminar, steady, irrotational flow leads to Bernoulli's equation. It states that the sum of the fluid pressure, potential, and kinetic energy per unit volume is constant along a streamline.
All the terms in the equation have the dimension of energy per unit volume. The kinetic energy per unit volume is called the kinetic energy density, and the potential energy per unit volume is...
All the terms in the equation have the dimension of energy per unit volume. The kinetic energy per unit volume is called the kinetic energy density, and the potential energy per unit volume is...
8.9K


